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

Execution · Competitive PvP
Blockbuster 2009 sequel famous for killstreak chains and frantic multiplayer.

Execution · Competitive PvP
Outplaying a human opponent through input precision and constant tactical guessing.
Call of Duty: Modern Warfare 2 leans Execution (Competitive PvP); FIFA 22 leans Execution (Competitive PvP).
Call of Duty: Modern Warfare 2 leans a little harder on execution, though the gap is small.
Call of Duty: Modern Warfare 2
Fast time-to-kill rewards raw aim and reflex
FIFA 22
Perfect inputs win skill moves, timed finishing and defending
FIFA 22 leans a little harder on reads, though the gap is small.
Call of Duty: Modern Warfare 2
Outguessing human rotations and flanks
FIFA 22
Outguessing a human's passing and defensive habits is the edge
FIFA 22 leans a little harder on variance, though the gap is small.
Call of Duty: Modern Warfare 2
Spawn flips and killstreak randomness
FIFA 22
Deflections, ref calls and pack luck inject real randomness
Call of Duty: Modern Warfare 2 leans a little harder on optimization, though the gap is small.
Call of Duty: Modern Warfare 2
Killstreak economy, loadout and map knowledge
FIFA 22
Formations, tactics and squad building sit underneath the duel
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.