head to head
Neither is simply harder - they are hard in different places. Grand Theft Auto V demands more reads; Shadow Warrior (2013) demands more execution.

Execution · Practiced Mastery
Sandbox crime playground spanning shooting, driving, and a persistent online economy.

Execution · Practiced Mastery
A sword-and-gun action shooter rewarding combo timing mastery and careful upgrade investment against scripted demon hordes.
Grand Theft Auto V leans Execution (Practiced Mastery); Shadow Warrior (2013) leans Execution (Practiced Mastery).
Shadow Warrior (2013) leans clearly harder on execution.
Grand Theft Auto V
Driving and shooting demand decent inputs.
Shadow Warrior (2013)
Sword combos and gunplay require precise timing and input chaining
Grand Theft Auto V leans clearly harder on reads.
Grand Theft Auto V
Online PvP exists but mostly gear/positioning, not modeling.
Shadow Warrior (2013)
All enemies are scripted demons with fixed attack patterns
Shadow Warrior (2013) leans a little harder on variance, though the gap is small.
Grand Theft Auto V
Some mission and lobby randomness.
Shadow Warrior (2013)
Upgrade drop randomness introduces mild run-to-run variance
Shadow Warrior (2013) leans clearly harder on optimization.
Grand Theft Auto V
Heists, money loops, builds learnable.
Shadow Warrior (2013)
Ki power and upgrade tree investment form a meaningful build layer
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.