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 · Competitive PvP
Football execution and human mind-games layered over tactical formation play.

Reads · Competitive PvP
Anime arena fighter where managing the substitution gauge is the real duel.
International Superstar Soccer Pro 98 leans Execution (Competitive PvP); Naruto Shippuden: Ultimate Ninja Storm 4 leans Reads (Competitive PvP).
International Superstar Soccer Pro 98 leans a little harder on execution, though the gap is small.
International Superstar Soccer Pro 98
First-touch timing and finishing demand practiced hands
Naruto Shippuden: Ultimate Ninja Storm 4
Simple inputs; movement and substitution timing matter
Naruto Shippuden: Ultimate Ninja Storm 4 leans a little harder on reads, though the gap is small.
International Superstar Soccer Pro 98
Versus matches hinge on outguessing a human defender
Naruto Shippuden: Ultimate Ninja Storm 4
Versus humans, baiting substitutions is the core game
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
International Superstar Soccer Pro 98
Bounces and deflections add bounded match chaos
Naruto Shippuden: Ultimate Ninja Storm 4
Minor support-assist chaos
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
International Superstar Soccer Pro 98
Formations and set-piece routines have learnable best answers
Naruto Shippuden: Ultimate Ninja Storm 4
Team composition and matchup knowledge
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.
full breakdown
International Superstar Soccer Pro 98 →
full breakdown
Naruto Shippuden: Ultimate Ninja Storm 4 →