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

Execution · Practiced Mastery
An open-zone Sonic experiment with cyberspace stages.

Execution · Practiced Mastery
A cinematic desert-bound adventure of shootouts, brawls, and sinking-ship set pieces.
Sonic Frontiers leans Execution (Practiced Mastery); Uncharted 3: Drake's Deception leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Sonic Frontiers
Boost-running and combat at speed
Uncharted 3: Drake's Deception
Gunfights, melee, and chases need steady hands
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Sonic Frontiers
Scripted enemies
Uncharted 3: Drake's Deception
Scripted enemies; multiplayer adds a trace
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Sonic Frontiers
Static open zones
Uncharted 3: Drake's Deception
Linear authored adventure
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Sonic Frontiers
Skill tree and stat farming
Uncharted 3: Drake's Deception
Learning encounters and routes solves the campaign
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.