head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is variance, 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
Football sim testing execution and opponent reading under a studied tactical meta.
Brawl Stars leans Execution (Competitive PvP); FIFA 21 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
FIFA 21
Skill moves and finishing mechanics demand practiced hands
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
FIFA 21
Outguessing a human's defensive shape and attacking patterns is central
FIFA 21 leans a little harder on variance, though the gap is small.
Brawl Stars
Bush ambushes and power-cube spawns hide information
FIFA 21
Deflections, finishing RNG and pack luck colour outcomes
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Brawl Stars
Brawler matchups and map strategy are learnable
FIFA 21
Meta formations, custom tactics and squad building are studied deeply
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.