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

Optimization · Pure Optimization
A supernatural teen drama where dialogue timing shapes relationships against a fixed mystery structure.

Optimization · Pure Optimization
The portal-gun puzzle game whose solutions are everything.
Oxenfree leans Optimization (Pure Optimization); Portal leans Optimization (Pure Optimization).
Portal leans clearly harder on execution.
Oxenfree
Radio tuning and walking demand no physical skill
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.
Oxenfree
Supernatural narrative with scripted ghost behaviour
Portal
No adversary modeling player.
Oxenfree leans clearly harder on variance.
Oxenfree
Dialogue timing creates minor branching uncertainty
Portal
Deterministic chambers; no randomness.
Portal leans clearly harder on optimization.
Oxenfree
Relationship and dialogue choices converge toward fixed endings
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.