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.

Optimization · Practiced Mastery
A sprawling open-world crime epic with RPG-style character stats across a whole state.

Optimization · Pure Optimization
The Wii and PSP entry reworking Tenchu into deliberate puzzle-flavored shadow stealth.
Grand Theft Auto: San Andreas leans Optimization (Practiced Mastery); Tenchu: Shadow Assassins leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Grand Theft Auto: San Andreas
Flying school and drive-bys need decent hands
Tenchu: Shadow Assassins
Simplified controls shift weight off raw dexterity
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Grand Theft Auto: San Andreas
Gang AI is scripted, never adaptive
Tenchu: Shadow Assassins
Guards follow rigid scripted vision cones
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Grand Theft Auto: San Andreas
Territory wars and traffic add light randomness
Tenchu: Shadow Assassins
Little randomness once a level is scouted
Tenchu: Shadow Assassins leans a little harder on optimization, though the gap is small.
Grand Theft Auto: San Andreas
Stats, gym, weapon skill, and routes reward systematic play
Tenchu: Shadow Assassins
Shadow paths and tool use make missions puzzle-like
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.