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 · Practiced Mastery
Underwater dogfighting testing piloting and aim through scripted missions.

Execution · Pure Mechanics
Arcade driving that tests cornering execution over a small set of memorisable tracks.
AquaNox leans Execution (Practiced Mastery); Need for Speed II leans Execution (Pure Mechanics).
Need for Speed II leans a little harder on execution, though the gap is small.
AquaNox
Six-degree underwater dogfighting demands piloting and aim
Need for Speed II
Cornering and throttle control decide every race
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
Need for Speed II
AI racers follow rubber-banded scripts, not minds
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
Need for Speed II
Tracks are fixed; nothing meaningful is hidden
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
Need for Speed II
Learning six tracks' racing lines and car choice
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.