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.

Optimization · Pure Optimization
A faction-driven RPG-shooter where build and route planning shape every ending.

Optimization · Pure Optimization
Touch-controlled DS Zelda centered on re-running a timed stealth dungeon ever faster.
Fallout: New Vegas leans Optimization (Pure Optimization); The Legend of Zelda: Phantom Hourglass leans Optimization (Pure Optimization).
Fallout: New Vegas leans a little harder on execution, though the gap is small.
Fallout: New Vegas
Shooter inputs with VATS assist
The Legend of Zelda: Phantom Hourglass
Stylus controls are simple and forgiving
Fallout: New Vegas leans a little harder on reads, though the gap is small.
Fallout: New Vegas
Scripted factions and enemies
The Legend of Zelda: Phantom Hourglass
Phantoms patrol fixed routes
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Fallout: New Vegas
Some loot and crit RNG
The Legend of Zelda: Phantom Hourglass
Sea exploration unknowns first run
Fallout: New Vegas leans a little harder on optimization, though the gap is small.
Fallout: New Vegas
Faction routing, perks, builds heavily rewarded
The Legend of Zelda: Phantom Hourglass
Temple of the Ocean King rewards optimized repeat routing
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.