head to head
Neither is simply harder - they are hard in different places. Pokémon Sword demands more variance; Portal demands more execution.

Optimization · Pure Optimization
Galar-region Pokémon adding open Wild Area exploration and stadium Dynamax battles.

Optimization · Pure Optimization
The portal-gun puzzle game whose solutions are everything.
Pokémon Sword leans Optimization (Pure Optimization); Portal leans Optimization (Pure Optimization).
Portal leans clearly harder on execution.
Pokémon Sword
Turn-based menus
Portal
Portal placement timing modest.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Pokémon Sword
Gym AI is static
Portal
No adversary modeling player.
Pokémon Sword leans clearly harder on variance.
Pokémon Sword
Wild Area spawns and raid rolls
Portal
Deterministic chambers; no randomness.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Pokémon Sword
Dynamax timing and team building decide 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.