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

Execution · Pure Mechanics
Twitchy miniature racing where handling beats strategy on chaotic tabletop tracks.

Execution · Pure Mechanics
A 3D platformer whose joy lives in tight movement and capture-driven traversal.
Micro Machines World Series 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.
Micro Machines World Series
Tiny-car handling on cramped tabletop tracks is twitch-heavy
Super Mario Odyssey
Precise platforming and capture-move tech ceiling.
Micro Machines World Series leans clearly harder on reads.
Micro Machines World Series
Human racers can be baited with weapons and blocks
Super Mario Odyssey
No adaptive opponents whatsoever.
Micro Machines World Series leans clearly harder on variance.
Micro Machines World Series
Pickup spawns and battle chaos add randomness
Super Mario Odyssey
Almost no randomness in level design.
Super Mario Odyssey leans clearly harder on optimization.
Micro Machines World Series
Track knowledge is shallow and learned quickly
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.