Honkai: Star RailBronyaBest build, teams and other guides

Best Light Cones

Best Light Cones

1

But the Battle Isn't Over(S1)

Increases the wearer's Energy Regeneration Rate by 10/12/14/16/18% and regenerates 1 Skill Point when the wearer uses their Ultimate on an ally. This effect can be triggered after every 2 uses of the wearer's Ultimate. When the wearer uses their Skill, the next ally taking action (except the wearer) deals 30/35/40/45/50% more DMG for 1 turn(s).

Source: Stellar Warp

A top option for characters that advance others via their skill, guaranteeing the DMG% boost of this Cone. Useful even on characters without the ability, thanks to the Energy Regen and skill point generation.

2

Past and Future(S5)

When the wearer uses their Skill, then the next ally taking action (except the wearer) deals 16/20/24/28/32% increased DMG for 1 turn(s).

Source: Echo of War  | Forgotten Hall Store  | Mission Reward

F2P option and alternative to But The Battle Isn't Over for characters that advance others via their Skill, guaranteeing the DMG% boost of this Cone.

Special Light Cones

Alternative or more specialized Light Cones that also are viable options for the character.

Dance! Dance! Dance!(S5)

When the wearer uses their Ultimate, all allies' actions are Advanced Forward by 16/18/20/22/24%

Source: Stellar Warp

Allows characters with high Speed and/or an accessible Ultimate to grant substantial action boosts to themselves and the team allowing for higher Speed (and cycle) breakpoints. Strongest on characters who can access their Ultimate at least once every 3 (but ideally 2) actions. Specifically strong when combined with other additional action advances or energy generation. When playing Bronya according to the -1 Speed build exercise caution when using this set bonus as it can ruin your Speed tuning unless carefully managed.

Best Relics

Best Relic Sets show the best sets that support the main character playstyle and work out of the box while the Special Relic Sets either are situational, support an alternative playstyle or are targeted toward min-maxers. The percentage numbers showcase the relative DPS increase when you take into account the set bonus only. For some characters there's no DPS (or its equivalent) available and in that case we listed the sets in the order of priority.

Best Relic Sets

1

Sacerdos' Relived Ordeal

(2)

Increases SPD by 6%.

(4)

When using Skill or Ultimate on one ally target, increases the ability target's CRIT DMG by 18%, lasting for 2 turn(s). This effect can stack up to 2 time(s).

Incredibly powerful set for characters with Ultimates and or Skills which target a single ally and who work well in teams with a sole damage dealer who can benefit from CRIT DMG.

2

Messenger Traversing Hackerspace

(2)

Increases SPD by 6%.

(4)

When the wearer uses their Ultimate on an ally, SPD for all allies increases by 12% for 1 turn(s). This effect cannot be stacked.

Flex

If you can't put together a top recommended 4P set with satisfactory sub/main stats, mix and match the 2P Bonuses from the following instead:

• 

  Sacerdos' Relived Ordeal
  [Speed +6%]
• Rainbow set - if you have great pieces with Speed from other sets, you can use them here.

Special Relic Sets

Messenger Traversing Hackerspace

(2)

Increases SPD by 6%.

(4)

When the wearer uses their Ultimate on an ally, SPD for all allies increases by 12% for 1 turn(s). This effect cannot be stacked.

Good team wide supportive option for characters with Ultimates which target allies. With this set equipped Ultimates are best timed carefully to ensure the Speed buff is active on key members for as long as possible. When playing Bronya according to the -1 Speed build exercise caution when using this set bonus as it can ruin your Speed tuning unless carefully managed (challenging).

Eagle of Twilight Line

(2)

Increases Wind DMG by 10%.

(4)

After the wearer uses Ultimate, their action is Advanced Forward by 25%.

Allows characters with accessible Ultimates to reach higher Speed (and cycle) breakpoints compared to just stacking Speed. Strongest on characters with powerful ultimate related effects or who can access their ultimate at least once every 3 (but ideally 2) actions. Particularly strong when combined with other action advancement effects. When playing Bronya according to the -1 Speed build exercise caution when using this set bonus as it can ruin your Speed tuning unless carefully managed (challenging).

Best Planetary Sets

1

Broken Keel

(2)

Increases the wearer's Effect RES by 10%. When the wearer's Effect RES is at 30% or higher, all allies' CRIT DMG increases by 10%.

An option for supports stacking Effect RES, while also increasing the entire team's CRIT DMG. Requires at least 30% Effect RES to activate.

The following Planars are all usable and have their own strength and weaknesses when looking for team-based supportive effects.

• 

  Fleet of the Ageless
  - Ideal for supporting teams that scale on ATK.
• 

  Penacony, Land of the Dreams
  - Top option for supporting teams with the same Element as the wearer, and for its Energy Regen.
• 

  Lushaka, the Sunken Seas
  - Top option for Supporting a single ATK-scaling DPS, and for its Energy Regen.

Special Planetary Sets

Sprightly Vonwacq

(2)

Increases the wearer's Energy Regeneration Rate by 5%. When the wearer's SPD reaches 120 or higher, the wearer's action is Advanced Forward by 40% immediately upon entering battle.

Incredibly potent option for buff/debuff based characters. The advance from this set allows the wearer to apply their buffs/debuffs before the rest of the team acts, accelerate rotations, allows access to ultimates closer to the start of the fight and also grants Energy Regen - a valuable stat for many supports.

Best Stats

Body

CRIT DMG

Feet

Speed

Planar Sphere

HP%

>

DEF%

Link Rope

Energy Regen Rate

Substats:

SPD (Until breakpoint) > CRIT DMG > HP = DEF > Effect RES% (30% If Keel)

Build comments

Can be played 2 ways, either Tune her SPD to be 1 below main DPS and spam Skill, or maximize her SPD to alternate between Basics and Skills to remain SP Neutral.

Recommended endgame stats

• HP: 3000 - 4000+

• DEF: 800 - 1100+

• SPD: 1-2 Speed slower than carry / 160+ (0 Speed Carry)

• ENERGY REGEN: 19.44%+

• CRIT DMG: 175 - 210%+

Traces priority

Skills priority:

Skill > Ultimate > Talent > Basic

Major Traces priority:

Command (A2) > Military Might (A6) > Battlefield (A4)

Character	Notes
	Blade being a DPS who rarely uses any Skill Points allows Bronya to always skill on him for maximizing DPS output, while also utilising all of her buffs, unlike other Harmonies who are always missing 1 or 2 buffs compared to Bronya.
	Jingliu has an awkward downtime after coming out of her Syzygy state, with a -1 Speed Bronya setup, you can skill with Jingliu into Bronya skilling her back up to go straight back into her Syzygy state and prolong her insane damage output.
	Boothill’s biggest weakness is his ramp-up time from being Single Target and needing to get his Pocket Trickshots done asap to deal the most damage. Bronya alleviates the ramp-up time if built with -1 Speed to Boothill, and can allow for much quicker rotations, at the cost of additional Skill Point consumption.

The teams in the section are generated based on the current Memory of Chaos data we have gathered. If you want to see more statistics about the mode, check the MoC/PF/AS Statistics tab.

Rank 23

App. rate: 1.14%

Avg. cycles: 7.24

Rank 32

App. rate: 0.68%

Avg. cycles: 5.67

Rank 69

App. rate: 0.29%

Avg. cycles: 7

Rank 73

App. rate: 0.27%

Avg. cycles: 8.11

Rank 75

App. rate: 0.26%

Avg. cycles: 0.25

Rank 85

App. rate: 0.23%

Avg. cycles: 99.99

Rank 97

App. rate: 0.19%

Avg. cycles: 7.56

Rank 110

App. rate: 0.17%

Avg. cycles: 8.43

Rank 110

App. rate: 0.17%

Avg. cycles: 99.99

Rank 110

App. rate: 0.17%

Avg. cycles: 8.73

This section contains information about Bronya performance in the latest Memory of Chaos cycle (2.5), latest Pure Fiction (2.6) and the latest Apocalyptic Shadow (2.6), and the commonly used Relics and Cones in both modes. The page will be automatically updated every 2 weeks once enough data is gathered in the current cycle.

• For MoC, the last update happened on 19.10.2024 and the data below is based on 16686 accounts (8453 random we have scanned and 8233 self-reported). We have scanned 1m accounts in EU, NA and Asia regions and out of those, 5086 cleared MoC 12.
• For PF, the last update happened on 15.11.2024 and the data below is based on 2462 accounts (4270 random we have scanned and 8192 self-reported). We have scanned 1m accounts in EU, NA and Asia regions and out of those, 3073 cleared Pure Fiction 4.
• For AS, the last update happened on 01.11.2024 and the data below is based on 12010 accounts (4153 random we have scanned and 7857 self-reported). We have scanned 1m accounts in EU, NA and Asia regions and out of those, 3321 cleared Apocalyptic Shadow 4.

If you want to share your clear information with us, you simply need to fill the form below and provide us with your UID and make your Hoyo profile public - we will automatically parse the MoC/PF clear information from your profile after that!

Characters are ranked with appearance rate, which is how often a character was used in Memory of Chaos by the players who we have scanned, regardless of whether they own the character or not. Ownership rate currently cannot be obtained.

90.81%

86.53%

75.44%

71.17%

64.57%

59.65%

43.34%

37.57%

31.02%

27.58%

25.79%

25.4%

19.35%

18.63%

15.88%

12.75%

9.77%

9.37%

9.3%

7.91%

6.86%

6.53%

6.41%

5.44%

5%

4.95%

4.59%

2.94%

2.94%

1.89%

1.43%

1.41%

1.38%

1.14%

1.13%

0.64%

0.56%

0.5%

0.42%

0.37%

0.22%

0.2%

0.18%

0.13%

0.11%

0.1%

0.09%

0.08%

0.07%

0.05%

0.04%

0.03%

0.03%

0.02%

0.02%

0.01%

0.01%

0%

0%

Characters are ranked with appearance rate, which is how often a character was used in Pure Fiction by the players who we have scanned, regardless of whether they own the character or not. Ownership rate currently cannot be obtained.

89.21%

72.45%

59.78%

58.04%

54.33%

46.2%

45.37%

44.38%

39.05%

37.81%

31.24%

30.65%

30.62%

23.22%

20.63%

15.88%

12.42%

10.96%

10.95%

9.72%

8.58%

7.36%

5.52%

4.72%

3.4%

3.13%

3.1%

2.99%

2.87%

2.52%

2.25%

1.64%

1.37%

1.23%

1.12%

1.06%

0.89%

0.87%

0.56%

0.48%

0.29%

0.26%

0.22%

0.12%

0.11%

0.08%

0.08%

0.08%

0.03%

0.02%

0.02%

0.01%

0.01%

0%

0%

0%

0%

0%

0%

0%

Characters are ranked with appearance rate, which is how often a character was used in Apocalyptic Shadow by the players who we have scanned, regardless of whether they own the character or not. Ownership rate currently cannot be obtained.

89.76%

85.38%

74.88%

62.88%

61.33%

59.65%

44.57%

39.9%

36.16%

31.41%

25.06%

24.01%

18.03%

16.79%

15.7%

15.43%

11%

9.94%

9.28%

8.83%

7.79%

6.64%

6.26%

5.69%

5.46%

4.56%

4.19%

2.95%

2.93%

2.77%

2.4%

1.36%

0.96%

0.86%

0.74%

0.73%

0.64%

0.62%

0.56%

0.37%

0.29%

0.23%

0.2%

0.15%

0.14%

0.09%

0.07%

0.05%

0.05%

0.05%

0.03%

0.03%

0.02%

0.02%

0.02%

0.01%

0%

0%

0%

0%

This section lists the characters that were most commonly paired with Bronya in the current phase of Memory of Chaos.

35.44%

27.3%

26.87%

26.02%

20.02%

16.06%

15.95%

13.49%

This section lists the characters that were most commonly paired with Bronya in the current phase of Pure Fiction.

37.05%%

23.61%%

22.95%%

16.72%%

16.07%%

15.08%%

15.08%%

14.43%%

This section lists the characters that were most commonly paired with Bronya in the current phase of Apocalyptic Shadow.

41.77%

29.5%

26.24%

21.58%

20.34%

19.72%

17.7%

17.7%

Eidolons

Eidolons data comes from players we have scanned who used Bronya in the current MoC cycle (934), in the current PF cycle (305) or in the current AS cycle (644) and had the character placed in their Profile.

11.66%

8.33 cyc.

Eidolon 0

21.45%

7.93 cyc.

Eidolon 1 - Hone Your Strength

Using Bronya's Skill has a 50% fixed chance of recovering 1 Skill Point. This effect has a 1 turn cooldown.

21.85%

7.83 cyc.

Eidolon 2 - Quick March

When using Skill, the target ally's SPD increases by 30% after taking action, lasting for 1 turn.

16.25%

7.89 cyc.

Eidolon 3 - Bombardment

Ultimate Lv. +2, up to a maximum of Lv. 15. Talent Lv. +2, up to a maximum of Lv. 15.

14.18%

6 cyc.

Eidolon 4 - Take by Surprise

After an ally uses Basic ATK on an enemy with Wind Weakness, Bronya immediately launches a follow-up attack on the target, dealing Wind DMG equal to 80% of Bronya's Basic ATK DMG. This effect can only be triggered 1 time per turn.

7.87%

6.5 cyc.

Eidolon 5 - Unstoppable

Skill Lv. +2, up to a maximum of Lv. 15. Basic ATK Lv. +1. up to a maximum of Lv. 10.

6.74%

6 cyc.

Eidolon 6 - Piercing Rainbow

The duration of the DMG Boost effect placed by the Skill on the target ally increases by 1 turn(s).

Light Cones

Light Cones are ranked with usage rate among the players we have scanned who used Bronya in the current MoC cycle (934), in the current PF cycle (305) or in the current AS cycle (644) and had the character placed in their Profile.

71.05%

7.59 cyc.

But the Battle Isn't Over

Increases the wearer's Energy Regeneration Rate by 10/12/14/16/18% and regenerates 1 Skill Point when the wearer uses their Ultimate on an ally. This effect can be triggered after every 2 uses of the wearer's Ultimate. When the wearer uses their Skill, the next ally taking action (except the wearer) deals 30/35/40/45/50% more DMG for 1 turn(s).

Source: Stellar Warp

11.93%

7.82 cyc.

Past and Future

When the wearer uses their Skill, then the next ally taking action (except the wearer) deals 16/20/24/28/32% increased DMG for 1 turn(s).

Source: Echo of War  | Forgotten Hall Store  | Mission Reward

11.2%

7.88 cyc.

Dance! Dance! Dance!

When the wearer uses their Ultimate, all allies' actions are Advanced Forward by 16/18/20/22/24%

Source: Stellar Warp

1.66%

99.99 cyc.

Planetary Rendezvous

Upon battle entry, if an ally deals the same DMG Type as the wearer, DMG dealt increases by 12/15/18/21/24%.

Source: Stellar Warp

1.16%

5.75 cyc.

Carve the Moon, Weave the Clouds

At the start of the battle and whenever the wearer's turn begins, one of the following effects is applied randomly: All allies' ATK increases by 10/12.5/15/17.5/20%, all allies' CRIT DMG increases by 12/15/18/21/24%, or all allies' Energy Regeneration Rate increases by 6/7.5/9/10.5/12%. The applied effect cannot be identical to the last effect applied, and will replace the previous effect. The applied effect will be removed when the wearer has been knocked down. Effects of the similar type cannot be stacked.

Source: Nameless Glory

1.07%

8 cyc.

Meshing Cogs

After the wearer uses attacks or gets hit, additionally regenerates 4/5/6/7/8 Energy. This effect can only be triggered 1 time per turn.

Source: Stellar Warp

0.62%

99.99 cyc.

Past Self in Mirror

Increases the wearer's Break Effect by 60/70/80/90/100%. After the wearer uses their Ultimate, increases all allies' DMG by 24/28/32/36/40%, lasting for 3 turns. Should the wearer's Break Effect exceed or equal 150%, 1 Skill Point will be recovered. At the start of each wave, immediately regenerates 10/12.5/15/17.5/20 Energy for all allies. Effects of the same type cannot stack.

Source: Event Warp (limited)

0.34%

99.99 cyc.

Mediation

Upon battle entry, all allies receive 12/14/16/18/20 increased SPD for 1 turn(s).

Source: Stellar Warp

0.34%

99.99 cyc.

Memories of the Past

Increases the wearer's Break Effect by 28/35/42/49/56%. When the wearer attacks, additionally regenerates 4/5/6/7/8 Energy. This effect can only be triggered 1 time per turn.

Source: Stellar Warp

0.16%

99.99 cyc.

For Tomorrow's Journey

Increases the wearer's ATK by 16/20/24/28/32%. After the wearer uses their Ultimate, increases their DMG dealt by 18/21/24/27/30%, lasting for 1 turn.

Source: Mission Reward

Relic Sets

Relic Sets are ranked with usage rate among the players we have scanned who used Bronya in the current MoC cycle (934), in the current PF cycle (305) or in the current AS cycle (644) and had the character placed in their Profile. The results are limited to top 5 combinations. Flex means 2 random Relic pieces that don't combine into a Set.

Relic Sets

35.34%

Messenger Traversing Hackerspace

(2)

Increases SPD by 6%.

(4)

When the wearer uses their Ultimate on an ally, SPD for all allies increases by 12% for 1 turn(s). This effect cannot be stacked.

10.66%

Messenger Traversing Hackerspace

(2)

Increases SPD by 6%.

(4)

When the wearer uses their Ultimate on an ally, SPD for all allies increases by 12% for 1 turn(s). This effect cannot be stacked.

Flex

10.26%

Messenger Traversing Hackerspace

(2)

Increases SPD by 6%.

(4)

When the wearer uses their Ultimate on an ally, SPD for all allies increases by 12% for 1 turn(s). This effect cannot be stacked.

Flex

6.51%

Eagle of Twilight Line

(2)

Increases Wind DMG by 10%.

(4)

After the wearer uses Ultimate, their action is Advanced Forward by 25%.

5.6%

Sacerdos' Relived Ordeal

(2)

Increases SPD by 6%.

(4)

When using Skill or Ultimate on one ally target, increases the ability target's CRIT DMG by 18%, lasting for 2 turn(s). This effect can stack up to 2 time(s).

Planetary Sets

61.26%

Broken Keel

(2)

Increases the wearer's Effect RES by 10%. When the wearer's Effect RES is at 30% or higher, all allies' CRIT DMG increases by 10%.

12%

Sprightly Vonwacq

(2)

Increases the wearer's Energy Regeneration Rate by 5%. When the wearer's SPD reaches 120 or higher, the wearer's action is Advanced Forward by 40% immediately upon entering battle.

6.2%

Penacony, Land of the Dreams

(2)

Increases wearer's Energy Regeneration Rate by 5%. Increases DMG for all other allies with the same DMG Type as the wearer by 10%.

4.33%

Forge of the Kalpagni Lantern

(2)

Increase the wearer's SPD by 6%. When the wearer hits enemy targets with Fire Weakness, the wearer's Break Effect increases by 40%, lasting for 1 turn(s).

3.11%

Lushaka, the Sunken Seas

(2)

Increases the wearer's Energy Regeneration Rate by 5%. If the wearer is not the first character in the team lineup, then increase the ATK of the first character in the team lineup by 12%.

Relic Stats

Relic Stats are shown based on the Relics used by the players we have scanned who used Bronya in the current MoC cycle (934), in the current PF cycle (305) or in the current AS cycle (644) and had the character placed in their Profile.

Main stats

Body

CRIT DMG

- 88.84%

HP

- 4.1%

DEF

- 2.69%

Feet

Speed

- 97.64%

ATK

- 1.39%

Planar Sphere

HP

- 52.96%

DEF

- 23.24%

Wind DMG

- 8.23%

Link Rope

Energy Regen Rate

- 93.01%

HP

- 2.91%

ATK

- 1.72%

Average stats

Average stats

HP

- 4120.6

ATK

- 1653.7

DEF

- 1341.11

Speed

- 148.88

CRIT Rate

- 10.85%

CRIT DMG

- 189.62%

Wind DMG

- 19.85%

Energy Regen Rate

- 26.87%

Effect RES

- 33.12%

Effect HIT Rate

- 9.17%

Break Effect

- 12.19%

Average sub stats

Average sub stats

HP

- 14.83%

ATK

- 13.15%

DEF

- 19.02%

Speed

- 20.23

CRIT Rate

- 5.85%

CRIT DMG

- 51.05%

Effect RES

- 16.2%

Effect HIT Rate

- 9.94%

Break Effect

- 11.63%

Other stats

Average stats

Character level - 79.72

Light Cone level - 79.06

Basic level - 4.25

Skill level - 10.02

Ultimate level - 10.27

Talent level - 9.37

TL;DR Who is better between Sparkle and Bronya comes down to the damage dealer of your choice and the specific setup you're using. To better understand the benefits and drawbacks of both, here is a full breakdown of what to expect from Sparkle and Bronya.

Buffs

Let's compare their buffs first:

When it comes to overall total buffs here are the standings (without Light Cones or Eidolons included):

• Sparkle (Quantum damage dealer): 186%
• Bronya: 183%
• Sparkle (Non-Quantum): 156%

But those are just the raw numbers and there are some important factors you need to keep in mind:

• Bronya cannot maintain her Ultimate buffs under most circumstances for more than 2/3's of damage dealers actions which reduces overall efficacy.
• The stat distribution of the buffs is different with Bronya offering more DMG% and Sparkle offering more CRIT DMG%. Depending on the damage dealer chosen one may prefer having higher of each of these stats, but as a general rule DMG% is generally the more desirable stats compared to CRIT DMG%.
• Sparkle only boosts her target by 50% half a turn where Bronya boosts by 100% a full turn. Something that looks like a landslide advantage for Bronya but comes with a catch because of our last reason - skill Point consumption and generation,
• Sparkle is completely skill point positive generating 0.33 skill points per action she performs but also grants a large influx of skill points at the start of combat. Bronya on the other hand is completely skill point negative at E0 without considering Light Cones (-1 skill points).

Playstyles - list

To full understand the impact of all points mentioned in the section above, it's time to compare the popular playstyles for both Bronya and Sparkle.

First let's go over the Hyperspeed setups for both:

Hyperspeed Bronya (160+ Speed)

• Consumes 1 SP every damage dealer action (-1 SP economy),
• Consumes 1 or more SP from damage dealer totaling at least -2 SP per action under most circumstances,
• Grants all buffs above with 66% ultimate uptime (under most circumstances),
• Grants current Speed to damage dealer (160 Speed),
• Carry requires 0 Speed investment (can run full DMG subs and DMG boots).

Summary: Skill point restrictive to run but not impossible. Made easier with Bronya Signature and E1 but requires careful SP management and two other SP positive team members.

Hyperspeed Sparkle (160+ Speed)

• Generates 0.33 SP every damage dealer action (+0.33 SP economy),
• Consumes 1 or more SP from the damage dealer totaling at least -0.66 SP per action under most circumstances,
• Grants 3 bonus SP at the start of battle,
• Grants all buffs above permanently,
• Grants current Speed to damage dealer (160 Speed),
• Carry requires 0 Speed investment (can run full DMG subs and DMG boots).

Summary: Skill point friendly to run, enabling almost any damage dealer to freely spam their skill without restriction. Can also support less SP friendly team mates such as Fu Xuan or E0 Huo Huo as the main healer without issue.

Now let's compare the -1 Speed setups for both:

-1 Speed Bronya (full skill spam)

• Consumes 1 SP every damage dealer action (-1 SP economy),
• Consumes 2 or more SP from the damage dealer totaling at least -3 SP per action under most circumstances,
• Grants 50% uptime on Skill buff and incredibly limited uptime of Ultimate,
• Grants double actions (2x Speed or double damage),
• Requires the carry to be 1 Speed faster than Bronya (usually 135).

Summary: This way of playing Bronya is almost impossible to run for most damage dealers for any sustained amount of cycles. Even while playing the most skill point positive supports, such as Luocha, outside of 2 exceptions: Blade and Jingliu who cheat the skill point system and consume very limited skill points of their own.

-1 Speed Bronya (Basic > Skill)

• Consumes 1 SP every damage dealer action (-1 SP economy),
• Consumes 1 and gains 1 SP from the the damage dealer by using a basic attack on the non-Bronya buffed action and the skill on the Bronya buffed action. Totalling a net consumption of -1 SP under most circumstances,
• Grants 50% uptime on Skill buff and incredibly limited uptime of Ultimate,
• Grants double actions (but not double damage) as half the actions the damage dealer is taking are standard Basic Attacks. Worth noting these are not useless and the skill is being used in the fully buffed action but it still isn't close to double damage,
• Requires the carry to be 1 Speed faster than Bronya (usually 135).

Summary: Most skill point friendly way to play Bronya and most flexible with DPS that aren't Blade or Jingliu causing her not to consume to many skill points and still benefit the DPS greatly but at the cost of overall damage.

-1 Speed Sparkle

• Generates 0.33SP every damage dealer action (+0.33 SP economy),
• Consumes 1.5 or more SP from the damage dealer totaling at least -1.17SP per action under most circumstances (-3.5 SP every 3 actions sparkle takes),
• Grants 3 bonus SP at the start of battle,
• Grants Skill boost 66% of the time a high portion of the time (> 60%).
• Grants 50% More Actions,
• Requires the carry to be 1 Speed faster than Sparkle (usually 135).

Summary: Sacrifices Sparkle buff uptime and some of her skill point economy for converting the Speed transfer like interaction into 50% more actions.

Playstyles - conclusion

To conclude our comparison here is the meat of it:

• For characters that have no (or limited) access to DMG% increases, Bronya's buffs have an edge but for characters with high DMG% who might crave CRIT DMG% Sparkle performs better,
• The best supportive option of the builds listed above is the -1 Speed Bronya (full skill spam), but it requires the carry to use 2 skills and Bronya use 1 skill every action. And this is close to impossible to achieve outside of Blade and Jingliu but for these 2 characters Bronya is still the clear best in slot,
• The second best option is Hyperspeed Bronya / Hyperspeed Sparkle. They both feature high buff uptime (from Skill and Ultimate), while also boosting the action acceleration of the damage dealer and enabling him to use ATK% (or HP%) boots and focus his sub-stats away from Speed.Both setups are very close in performance and which is stronger numerically will depend on the damage dealer, sub-stats and Light Cones being used. But it's without a question that Hyperspeed Sparkle is substantially more skill point friendly than Hyperspeed Bronya, enabling the smooth use of sustains and supports that can't generate as many SP,
• Next in performance is the -1 Speed Sparkle build that can still sustain the skill spam playstyle of the damage dealer albeit with much more difficulty compared to the Hyperspeed Sparkle while still offering reasonable uptime on buffs and the 50% action multiplier,
• Last in performance is the Skill -> Basic Bronya that asks the dps to use 1 basic and then 1 skill after Bronya boosts them cutting their damage in many cases substantially (also with the cost of having low uptime on Bronya's buffs). This composition is the most SP friendly of all Bronya's options but lacks the buff uptime and skill usage of all 4 options putting it in last place.

You can see the comparison visualized here with a simulation of how each of the different builds impacts an endgame E0 S1 Imbibitor Lunae with Sparkle or Bronya as their only support over 8 actions. Observe the impact each build has on damage but also net skill points consumed by the combo (Sparkle's technique SP and Bronya Signature SP are included):

Disclaimer! We know that E0 Imbibitor Lunae isn't the best when played with Bronya, but we decided to use him as the example due to his excessive skill point consumption - which allows us to better showcase the difference between the setups.

Summary

Bronya is best for Blade and Jingliu as she can edge out Sparkle when both are being played in the Hyperspeed setup (when skill points aren't a concern) but Sparkle is close to (or even beats) Bronya in cases when CRIT DMG is valued over DMG% or when the damage dealer belongs to the Quantum element.

Still, the flexibility of Sparkle's SP positive nature and her ability to boost the damage dealer's output outside of their own turn (which is very important for FUA characters like Jing Yuan, Dr. Ratio or Clara) pushes her usefulness and makes her the more universal support compared to Bronya - and by a good amount despite her maximum ceiling being lower for some characters.