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
Reversal timing and pacing against an opponent baiting your counters.

Execution · Competitive PvP
Grapple-timing wrestling where couch matches hinge on outguessing the other player.
WWE 2K15 leans Execution (Competitive PvP); WWF Attitude leans Execution (Competitive PvP).
WWF Attitude leans a little harder on execution, though the gap is small.
WWE 2K15
Reversal timing windows decide most exchanges
WWF Attitude
Grapple timing and combo inputs decide exchanges
WWF Attitude leans a little harder on reads, though the gap is small.
WWE 2K15
Human opponents bait reversals and vary move timing
WWF Attitude
Versus humans, grapple attempts become a guessing duel
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
WWE 2K15
Chain-wrestling rock-paper-scissors minigames add randomness
WWF Attitude
Reversal windows add light chaos
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
WWE 2K15
Move sets, stamina and match pacing are learnable systems
WWF Attitude
Move-set knowledge and stamina management reward study
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.