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.

Optimization · Practiced Mastery
Open-world superagent sandbox about leveling skills and hunting 500 agility orbs.

Execution · Practiced Mastery
Zelda-meets-God-of-War action adventure starring the horseman War.
Crackdown leans Optimization (Practiced Mastery); Darksiders leans Execution (Practiced Mastery).
Darksiders leans a little harder on execution, though the gap is small.
Crackdown
Aim, driving, and rooftop leaping
Darksiders
combo-driven combat with dodge timing
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Crackdown
Gangs are static spawn sets
Darksiders
enemies are scripted
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Crackdown
Fixed world with placed collectibles
Darksiders
world and bosses are fixed
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Crackdown
Skill-orb routing and boss order planning
Darksiders
Zelda-style dungeons and upgrade routing
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.