head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Execution · Competitive PvP
Arena-fighter execution and couch-versus prediction across an enormous anime roster.

Execution · Competitive PvP
Punch timing and counter prediction in movie-licensed boxing.
Dragon Ball Z: Budokai Tenkaichi 2 leans Execution (Competitive PvP); Rocky Legends 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.
Dragon Ball Z: Budokai Tenkaichi 2
Beam clashes, vanish timing and arena movement reward fast hands
Rocky Legends
Punch timing and blocking windows carry every exchange
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Dragon Ball Z: Budokai Tenkaichi 2
Versus friends, baiting transformations and dodges matters
Rocky Legends
Human opponents feint and bait counters in versus
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Dragon Ball Z: Budokai Tenkaichi 2
Full movesets are public knowledge
Rocky Legends
Little randomness beyond minor damage rolls
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Dragon Ball Z: Budokai Tenkaichi 2
A 120-character roster of matchup and item knowledge
Rocky Legends
Training allocation and counter knowledge are plannable
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.