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.

Optimization · Pure Optimization
A VATS-heavy wasteland RPG won by perk and build optimization.

Optimization · Pure Optimization
Action-leaning Pokémon spinoff about catching in real time across ancient Hisui.
Fallout 3 leans Optimization (Pure Optimization); Pokémon Legends: Arceus 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.
Fallout 3
VATS-leaning combat, low aim demand
Pokémon Legends: Arceus
Real-time dodging, sneaking, and aimed throws
Fallout 3 leans a little harder on reads, though the gap is small.
Fallout 3
Scripted enemies
Pokémon Legends: Arceus
Wild and boss behavior is scripted
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Fallout 3
Loot rolls, SPECIAL checks
Pokémon Legends: Arceus
Spawn tables and outbreak randomness
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Fallout 3
Perk and build planning carries the run
Pokémon Legends: Arceus
Research tasks and agile-strong style choices reward planning
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.