head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Execution · Competitive PvP
Timing on the ball and outguessing the opposing player's tactics.

Execution · Competitive PvP
Reversal-timing duels dressed in wrestling spectacle, with light opponent prediction.
FIFA Soccer 06 leans Execution (Competitive PvP); WWE 2K14 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 06
First-touch control and shot timing decide chances
WWE 2K14
Reversal timing windows are the main physical test
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
FIFA Soccer 06
Human opponents vary attack patterns and bait tackles
WWE 2K14
Human opponents bait reversals; AI is mappable
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
FIFA Soccer 06
Bounces and keeper spills inject small randomness
WWE 2K14
Comeback mechanics add scripted swing
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
FIFA Soccer 06
Squad selection and tactics reward preparation
WWE 2K14
Knowing move properties and match-type rules pays off
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.