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

Execution · Pure Mechanics
Squad shooting against scripted hordes with light class-loadout decisions.

Execution · Practiced Mastery
Alternate-history alien-invasion shooter known for its inventive Chimeran arsenal.
Resident Evil: Operation Raccoon City leans Execution (Pure Mechanics); Resistance: Fall of Man 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.
Resident Evil: Operation Raccoon City
Third-person aim against zombie and soldier swarms carries the game
Resistance: Fall of Man
Aim and weapon handling against Chimera hordes.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Resident Evil: Operation Raccoon City
Versus modes add human prediction; campaign AI is scripted
Resistance: Fall of Man
Sizable competitive multiplayer added genuine human opposition.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Resident Evil: Operation Raccoon City
Infection mechanics and spawn chaos add mild unpredictability
Resistance: Fall of Man
Campaign unknowns on first pass.
Resistance: Fall of Man leans a little harder on optimization, though the gap is small.
Resident Evil: Operation Raccoon City
Class abilities and loadouts are a shallow solvable layer
Resistance: Fall of Man
Exotic weapon selection per encounter rewards system knowledge.
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.