head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is variance, and it is a single point.

Execution · Pure Mechanics
Spectacle hack-and-slash where reflexes and combo flow drive every fight.

Execution · Pure Mechanics
VR Half-Life where hand-presence interaction defines every fight.
God of War III leans Execution (Pure Mechanics); Half-Life: Alyx leans Execution (Pure Mechanics).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
God of War III
Combo execution and QTE timing carry combat.
Half-Life: Alyx
VR aim, reload, and grab inputs intense.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
God of War III
Bosses fully scripted spectacle.
Half-Life: Alyx
Combine and headcrabs scripted.
Half-Life: Alyx leans a little harder on variance, though the gap is small.
God of War III
Almost no randomness.
Half-Life: Alyx
Resource and encounter variance light.
God of War III leans a little harder on optimization, though the gap is small.
God of War III
Upgrade paths short and obvious.
Half-Life: Alyx
Few systems to tune.
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.