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 · Practiced Mastery
Stick execution and opponent prediction inside licensed tournament football.

Execution · Competitive PvP
Reversal timing and pacing against an opponent baiting your counters.
UEFA Champions League 2006–2007 leans Execution (Practiced Mastery); WWE 2K15 leans Execution (Competitive PvP).
UEFA Champions League 2006–2007 leans a little harder on execution, though the gap is small.
UEFA Champions League 2006–2007
Pass timing and shot placement decide most goals
WWE 2K15
Reversal timing windows decide most exchanges
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
UEFA Champions League 2006–2007
Human opponents bait tackles and disguise attacks
WWE 2K15
Human opponents bait reversals and vary move timing
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
UEFA Champions League 2006–2007
Deflections and AI bounces add match noise
WWE 2K15
Chain-wrestling rock-paper-scissors minigames add randomness
UEFA Champions League 2006–2007 leans a little harder on optimization, though the gap is small.
UEFA Champions League 2006–2007
Squad selection and tactical setup are solvable preparation
WWE 2K15
Move sets, stamina and match pacing are learnable systems
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.