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

Execution · Practiced Mastery
N64 spy FPS famed for gadget-heavy missions and bot-filled multiplayer.

Execution · Pure Mechanics
A late-90s mercenary FPS infamous for its graphic locational damage system.
Perfect Dark leans Execution (Practiced Mastery); Soldier of Fortune 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.
Perfect Dark
N64 manual aim and tight mission play
Soldier of Fortune
Fast twitch aim against fragile enemies decides everything
Perfect Dark leans a little harder on reads, though the gap is small.
Perfect Dark
Multiplayer and clever sims add some human-style adaptation
Soldier of Fortune
Multiplayer duels add a little human prediction
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Perfect Dark
Mission scripting fixed once learned
Soldier of Fortune
Campaign layouts and spawns are fixed
Perfect Dark leans a little harder on optimization, though the gap is small.
Perfect Dark
Objective routing on harder difficulty tiers
Soldier of Fortune
Weapon choice and level routes are quickly learned
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.