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.

Execution · Light / Casual
Cinematic interactive drama following a woman tethered to a ghostly entity.

Optimization · Light / Casual
A first-person mystery about a fire lookout in a Wyoming forest.
Beyond: Two Souls leans Execution (Light / Casual); Firewatch leans Optimization (Light / Casual).
Beyond: Two Souls leans a little harder on execution, though the gap is small.
Beyond: Two Souls
QTE prompts with forgiving failure states
Firewatch
Walking and radio dialogue only.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Beyond: Two Souls
No opponent; cinematic scenes
Firewatch
No adaptive opposition.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Beyond: Two Souls
Branching outcomes surprise first playthrough
Firewatch
Minor environmental discoveries.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Beyond: Two Souls
Choice outcomes mappable across replays
Firewatch
Few systems to optimize.
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.