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
Classic licensed football testing input control and opponent pattern reading.

Execution · Competitive PvP
An arcade wrestling fighter about throw timing and outguessing opponents in grapples.
FIFA Soccer 2005 leans Execution (Competitive PvP); Saturday Night Slam Masters 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 2005
Off-the-ball control and finishing timing are mechanical skill
Saturday Night Slam Masters
Grab, throw and special-move timing decide bouts
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
FIFA Soccer 2005
Human opponents adjust attack patterns across a match
Saturday Night Slam Masters
Human opponents adapt; grappling is a prediction battle
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
FIFA Soccer 2005
Bounces and keeper behaviour add minor chaos
Saturday Night Slam Masters
Little randomness once moves are learned
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
FIFA Soccer 2005
Formations and exploit plays of the era are learnable
Saturday Night Slam Masters
Move spacing and ring positioning are learnable
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.