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
An online multiplayer soccer game about positioning and outplaying human opponents.

Execution · Competitive PvP
Frantic small-arena duels testing reflexes and prediction of human opponents.
Soccer Online: Ball 3D leans Execution (Competitive PvP); Superfighters Deluxe leans Execution (Competitive PvP).
Superfighters Deluxe leans a little harder on execution, though the gap is small.
Soccer Online: Ball 3D
Controlling shots and movement precisely matters in matches
Superfighters Deluxe
Aim, blocks, throws and movement decide frantic small-arena fights
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Soccer Online: Ball 3D
Outguessing human opponents' passes and positioning is constant
Superfighters Deluxe
Human opponents constantly adapt positioning and weapon timing
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Soccer Online: Ball 3D
Some physics unpredictability but mostly skill-driven
Superfighters Deluxe
Random weapon spawns and destructible chaos shuffle fights
Soccer Online: Ball 3D leans a little harder on optimization, though the gap is small.
Soccer Online: Ball 3D
Team coordination and positioning tactics reward planning
Superfighters Deluxe
Map knowledge and weapon priorities are a thin layer
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.