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

Optimization · Pure Optimization
Grid-based dungeon crawler about riddles, secret buttons, and square-dancing around monsters.

Optimization · Pure Optimization
Zelda-starring adventure where summoning copied objects and monsters solves combat and puzzles alike.
Legend of Grimrock leans Optimization (Pure Optimization); The Legend of Zelda: Echoes of Wisdom leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Legend of Grimrock
Real-time grid strafing around slow monsters
The Legend of Zelda: Echoes of Wisdom
Light action; echoes fight for you
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Legend of Grimrock
Monsters chase on simple fixed logic
The Legend of Zelda: Echoes of Wisdom
Scripted enemies throughout
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Legend of Grimrock
Secrets hidden until found, then fixed
The Legend of Zelda: Echoes of Wisdom
First-run discovery of echoes and rifts
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Legend of Grimrock
Party builds, riddles, and pressure-plate puzzles dominate
The Legend of Zelda: Echoes of Wisdom
Choosing which copied object solves each room
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.