head to head
Neither is simply harder - they are hard in different places. Pokemon: Let's Go, Pikachu! demands more variance; Portal demands more execution.

Optimization · Pure Optimization
A streamlined Kanto remake blending classic battles with Pokemon GO-style motion-throw catching.

Optimization · Pure Optimization
The portal-gun puzzle game whose solutions are everything.
Pokemon: Let's Go, Pikachu! leans Optimization (Pure Optimization); Portal leans Optimization (Pure Optimization).
Portal leans clearly harder on execution.
Pokemon: Let's Go, Pikachu!
Motion-controlled ball throws add light timing skill
Portal
Portal placement timing modest.
Pokemon: Let's Go, Pikachu! leans a little harder on reads, though the gap is small.
Pokemon: Let's Go, Pikachu!
Trainers are scripted; minimal PvP focus
Portal
No adversary modeling player.
Pokemon: Let's Go, Pikachu! leans clearly harder on variance.
Pokemon: Let's Go, Pikachu!
Catch rolls and wild spawns bring luck
Portal
Deterministic chambers; no randomness.
Portal leans a little harder on optimization, though the gap is small.
Pokemon: Let's Go, Pikachu!
Simplified team building still decides battles
Portal
Pure puzzle-solving optimization.
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.