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

Execution · Pure Mechanics
A run-and-gun boss rush about dodging scripted patterns with tight inputs.

Execution · Pure Mechanics
A first-person cyberpunk slasher where everything dies in one hit, including you.
Cuphead leans Execution (Pure Mechanics); Ghostrunner 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.
Cuphead
Tight dodging and parry timing decide every boss.
Ghostrunner
One-hit-death parkour and slashing demand near-perfect inputs
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Cuphead
Bosses cycle scripted phases; no adaptation to player.
Ghostrunner
Enemy placements are fixed
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Cuphead
Minor attack-order shuffling between phases.
Ghostrunner
Deterministic levels
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Cuphead
Loadouts and boss phase order are fully learnable.
Ghostrunner
Route planning and enemy-order solutions define fast clears
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.