head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is optimization, and it is a single point.

Execution · Competitive PvP
Supercell's snappy top-down team brawler built around three-minute objective fights.

Execution · Competitive PvP
An anime fighting game testing execution and prediction against human opponents.
Brawl Stars leans Execution (Competitive PvP); Yu Yu Hakusho: Ghost Files - Dark Tournament leans Execution (Competitive PvP).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Brawl Stars
Aim, dodging, and ability timing in real time
Yu Yu Hakusho: Ghost Files - Dark Tournament
Combo timing and spacing matter in fast 2D fights
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Brawl Stars
Human teams rotate, bait supers, and adapt
Yu Yu Hakusho: Ghost Files - Dark Tournament
Human versus opponents drives prediction of attacks and blocks
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Brawl Stars
Bush ambushes and power-cube spawns hide information
Yu Yu Hakusho: Ghost Files - Dark Tournament
Some card-mode RNG and matchup chaos
Brawl Stars leans a little harder on optimization, though the gap is small.
Brawl Stars
Brawler matchups and map strategy are learnable
Yu Yu Hakusho: Ghost Files - Dark Tournament
Character movesets and matchups reward study
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.