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
Underwater dogfighting testing piloting and aim through scripted missions.

Execution · Practiced Mastery
A retro-styled action platformer with pogo-stick combat.
AquaNox leans Execution (Practiced Mastery); Shovel Knight 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.
AquaNox
Six-degree underwater dogfighting demands piloting and aim
Shovel Knight
Pogo combat and platforming need timing
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
AquaNox
Mission enemies attack on fixed scripts
Shovel Knight
Scripted boss patterns, not reads
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
AquaNox
Missions play out identically each attempt
Shovel Knight
Deterministic stages
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
AquaNox
Ship loadout and weapon choice add modest planning
Shovel Knight
Relic and upgrade choices shape runs
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.