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
Stick execution and outguessing a human defender, with tactics underneath.

Execution · Competitive PvP
The peak-era Konami football game prized for weighty, skill-driven match play.
FIFA Soccer 08 leans Execution (Competitive PvP); Pro Evolution Soccer 6 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 Soccer 08
Dribbling, timing tackles and finishing reward 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 08
Versus humans, baiting defenders and disguising attacks is core
Pro Evolution Soccer 6
Versus matches are constant feint and positioning prediction
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
FIFA Soccer 08
Ball physics adds bounce noise to single matches
Pro Evolution Soccer 6
Deflections and keeper spills add light randomness
Pro Evolution Soccer 6 leans a little harder on optimization, though the gap is small.
FIFA Soccer 08
Formations and squad selection matter but stay shallow
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.