head to head
Neither is simply harder - they are hard in different places. Portal demands more execution; The Great Ace Attorney 2: Resolve demands more variance.

Optimization · Pure Optimization
The portal-gun puzzle game whose solutions are everything.

Optimization · Pure Optimization
Courtroom logic puzzles testing deduction of fixed contradictions inside a scripted story.
Portal leans Optimization (Pure Optimization); The Great Ace Attorney 2: Resolve leans Optimization (Pure Optimization).
Portal leans clearly harder on execution.
Portal
Portal placement timing modest.
The Great Ace Attorney 2: Resolve
Presenting evidence takes no physical skill
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Portal
No adversary modeling player.
The Great Ace Attorney 2: Resolve
Witnesses are scripted; contradictions never adapt to you
The Great Ace Attorney 2: Resolve leans clearly harder on variance.
Portal
Deterministic chambers; no randomness.
The Great Ace Attorney 2: Resolve
Case truths are hidden only until the script reveals them
Portal leans a little harder on optimization, though the gap is small.
Portal
Pure puzzle-solving optimization.
The Great Ace Attorney 2: Resolve
Each trial is a fixed logic chain with one solution
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.