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.

Reads · Competitive PvP
Anime arena fighter where managing the substitution gauge is the real duel.

Execution · Competitive PvP
A wrestling game about timing grapples and, versus humans, reading reversals.
Naruto Shippuden: Ultimate Ninja Storm 4 leans Reads (Competitive PvP); WCW/nWo Thunder leans Execution (Competitive PvP).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Naruto Shippuden: Ultimate Ninja Storm 4
Simple inputs; movement and substitution timing matter
WCW/nWo Thunder
Grapple and strike timing decide exchanges
Naruto Shippuden: Ultimate Ninja Storm 4 leans a little harder on reads, though the gap is small.
Naruto Shippuden: Ultimate Ninja Storm 4
Versus humans, baiting substitutions is the core game
WCW/nWo Thunder
Human opponents must be anticipated and countered
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Naruto Shippuden: Ultimate Ninja Storm 4
Minor support-assist chaos
WCW/nWo Thunder
Reversal windows add some unpredictability
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Naruto Shippuden: Ultimate Ninja Storm 4
Team composition and matchup knowledge
WCW/nWo Thunder
Move-set knowledge and stamina management matter
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.