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 · Practiced Mastery
An aggressive soulslike about punishing fixed boss patterns with tight dodging.

Execution · Practiced Mastery
A stance-action RPG carried by ki-pulse timing and loot build optimization.
Bloodborne leans Execution (Practiced Mastery); Nioh leans Execution (Practiced Mastery).
Nioh leans a little harder on execution, though the gap is small.
Bloodborne
Aggressive dodges and rally timing demand sharp hands.
Nioh
Stance and ki-pulse timing demand inputs
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Bloodborne
Bosses follow fixed movesets; no model of you.
Nioh
Scripted enemies
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Bloodborne
Chalice dungeon layouts and drops add some randomness.
Nioh
Loot affix rolls
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Bloodborne
Builds, weapons, and boss patterns are studyable and solvable.
Nioh
Build crafting and stance routing reward planning
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.