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

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

Optimization · Pure Optimization
A streamlined Kanto remake blending classic battles with Pokemon GO-style motion-throw catching.
Fallout 3 leans Optimization (Pure Optimization); Pokemon: Let's Go, Pikachu! leans Optimization (Pure Optimization).
Fallout 3 leans a little harder on execution, though the gap is small.
Fallout 3
VATS-leaning combat, low aim demand
Pokemon: Let's Go, Pikachu!
Motion-controlled ball throws add light timing skill
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Fallout 3
Scripted enemies
Pokemon: Let's Go, Pikachu!
Trainers are scripted; minimal PvP focus
Pokemon: Let's Go, Pikachu! leans a little harder on variance, though the gap is small.
Fallout 3
Loot rolls, SPECIAL checks
Pokemon: Let's Go, Pikachu!
Catch rolls and wild spawns bring luck
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
Pokemon: Let's Go, Pikachu!
Simplified team building still decides battles
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.