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

Optimization · Pure Optimization
A perk-driven sci-fi RPG won by flaw selection and dialogue routing.

Optimization · Pure Optimization
A class-swapping JRPG carried by art-rotation and ouroboros build optimization.
The Outer Worlds leans Optimization (Pure Optimization); Xenoblade Chronicles 3 leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
The Outer Worlds
FPS-lite with time-dilation aim
Xenoblade Chronicles 3
Auto-attack with art-timing inputs
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
The Outer Worlds
Scripted enemies
Xenoblade Chronicles 3
Scripted enemies
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
The Outer Worlds
Loot rolls, dialogue check variance
Xenoblade Chronicles 3
Loot and gem rolls
Xenoblade Chronicles 3 leans a little harder on optimization, though the gap is small.
The Outer Worlds
Perks, flaws, dialogue routing rewarded
Xenoblade Chronicles 3
Class, art, and ouroboros builds deeply rewarded
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.