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
Football sim testing stick execution and reading a human opponent's tactical habits.

Execution · Competitive PvP
The peak-era Konami football game prized for weighty, skill-driven match play.
FIFA Soccer 11 leans Execution (Competitive PvP); Pro Evolution Soccer 6 leans Execution (Competitive PvP).
Pro Evolution Soccer 6 leans a little harder on execution, though the gap is small.
FIFA Soccer 11
Pass timing, dribbling and finishing demand stick skill
Pro Evolution Soccer 6
First touch, through balls, and dribbles demand precise control
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
FIFA Soccer 11
Human opponents' defensive habits and attacking patterns must be modelled
Pro Evolution Soccer 6
Versus matches are constant feint and positioning prediction
FIFA Soccer 11 leans a little harder on variance, though the gap is small.
FIFA Soccer 11
Deflections and keeper behaviour add bounded chaos
Pro Evolution Soccer 6
Deflections and keeper spills add light randomness
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
FIFA Soccer 11
Formations, tactics and squad knowledge shape matches
Pro Evolution Soccer 6
Formations and player roles are studyable
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.