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

Execution · Pure Mechanics
A two-minute test of joystick reflexes and simple punch-trading rhythm.

Execution · Pure Mechanics
A 3D platformer whose joy lives in tight movement and capture-driven traversal.
Boxing leans Execution (Pure Mechanics); Super Mario Odyssey leans Execution (Pure Mechanics).
Super Mario Odyssey leans a little harder on execution, though the gap is small.
Boxing
Joystick speed and punch timing decide the two-minute bout
Super Mario Odyssey
Precise platforming and capture-move tech ceiling.
Boxing leans clearly harder on reads.
Boxing
A human second player can be baited and predicted
Super Mario Odyssey
No adaptive opponents whatsoever.
Super Mario Odyssey leans a little harder on variance, though the gap is small.
Boxing
Nothing hidden or random in the ring
Super Mario Odyssey
Almost no randomness in level design.
Super Mario Odyssey leans clearly harder on optimization.
Boxing
Scoring rules are shallow; positioning tricks are quickly learned
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.