head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is reads, and it is a single point.

Execution · Practiced Mastery
A team arcade racer with no finish line, scoring takedowns and objectives in a rolling stampede.

Execution · Practiced Mastery
Managing air meter and shortcut routes at speed on memorised tracks.
Onrush leans Execution (Practiced Mastery); Sonic Riders leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Onrush
Boost management and aerial takedowns need car control
Sonic Riders
Air management, drift timing and shortcuts demand practiced hands
Onrush leans a little harder on reads, though the gap is small.
Onrush
Team-based human opponents in stampede modes
Sonic Riders
Versus humans there is mild positional jockeying
Onrush leans a little harder on variance, though the gap is small.
Onrush
Chaotic pack collisions and fodder spawns
Sonic Riders
Item and turbulence placement adds light randomness
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Onrush
Class roles and rush timing are learnable
Sonic Riders
Gear choice and shortcut routes reward track 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.