head to head
Neither is simply harder - they are hard in different places. Rocket League demands more reads; Super Mario Odyssey demands more optimization.

Execution · Pure Mechanics
Mechanical car-soccer where execution is the ceiling.

Execution · Pure Mechanics
A 3D platformer whose joy lives in tight movement and capture-driven traversal.
Rocket League leans Execution (Pure Mechanics); Super Mario Odyssey leans Execution (Pure Mechanics).
Rocket League leans clearly harder on execution.
Rocket League
Aerials, flicks, dribbles, pure mechanical ceiling
Super Mario Odyssey
Precise platforming and capture-move tech ceiling.
Rocket League leans clearly harder on reads.
Rocket League
Rotations and 50-50 reads against humans
Super Mario Odyssey
No adaptive opponents whatsoever.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Rocket League
Almost deterministic physics
Super Mario Odyssey
Almost no randomness in level design.
Super Mario Odyssey leans clearly harder on optimization.
Rocket League
Training routines, rotation theory
Super Mario Odyssey
Moon routes and movement tech 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.