head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Execution · Practiced Mastery
A first-person supernatural adventure cleansing a spirit-emptied Tokyo with elemental hand magic.

Execution · Practiced Mastery
An action RPG where narrative depth is paired with moderately solvable combat systems.
Ghostwire: Tokyo leans Execution (Practiced Mastery); NieR leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Ghostwire: Tokyo
Aimed ether weaving and core-grab timing
NieR
combat timing and dodges matter
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Ghostwire: Tokyo
Spirits attack on fixed scripts
NieR
scripted enemies, no adaptation
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Ghostwire: Tokyo
Light enemy spawn variation
NieR
loot and encounter randomness
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Ghostwire: Tokyo
Skill upgrades and ability usage are easily systematised
NieR
builds and side systems solvable
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.