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

Execution · Competitive PvP
Football sim testing execution and opponent reading under a studied tactical meta.

Execution · Competitive PvP
Artillery aim and turn planning against human opponents on destructible terrain.
FIFA 21 leans Execution (Competitive PvP); Worms Clan Wars 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.
FIFA 21
Skill moves and finishing mechanics demand practiced hands
Worms Clan Wars
Grenade arcs and ninja-rope control decide turns
FIFA 21 leans a little harder on reads, though the gap is small.
FIFA 21
Outguessing a human's defensive shape and attacking patterns is central
Worms Clan Wars
Anticipating human opponents' target priorities matters in clan play
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
FIFA 21
Deflections, finishing RNG and pack luck colour outcomes
Worms Clan Wars
Crate drops and terrain destruction add swing
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
FIFA 21
Meta formations, custom tactics and squad building are studied deeply
Worms Clan Wars
Weapon economy and positioning plans reward forethought
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.