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
FPS aim welded to a team economy of base-destruction priorities.

Execution · Competitive PvP
Substitution baiting against humans atop simple anime-fighter inputs and team picks.
Command & Conquer: Renegade leans Execution (Practiced Mastery); Naruto Shippuden: Ultimate Ninja Storm 2 leans Execution (Competitive PvP).
Command & Conquer: Renegade leans a little harder on execution, though the gap is small.
Command & Conquer: Renegade
FPS aim in infantry and vehicle fights carries the game
Naruto Shippuden: Ultimate Ninja Storm 2
Timing substitutions and combos matters but inputs are simple
Naruto Shippuden: Ultimate Ninja Storm 2 leans a little harder on reads, though the gap is small.
Command & Conquer: Renegade
Multiplayer base assaults involve predicting human team pushes
Naruto Shippuden: Ultimate Ninja Storm 2
Versus humans, baiting substitutions is the real layer
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Command & Conquer: Renegade
Maps and economy rules are fully known
Naruto Shippuden: Ultimate Ninja Storm 2
Nothing hidden once both characters are known
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Command & Conquer: Renegade
Credit economy and building-target priority decide C&C-mode matches
Naruto Shippuden: Ultimate Ninja Storm 2
Team composition and chakra management have solvable lines
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.