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 2D sandbox of procedurally generated planets driven by crafting progression.

Optimization · Pure Optimization
A dwarven survival-crafting expedition where managing ore, gear and bases outweighs swordplay.
Starbound leans Optimization (Pure Optimization); The Lord of the Rings: Return to Moria leans Optimization (Pure Optimization).
The Lord of the Rings: Return to Moria leans a little harder on execution, though the gap is small.
Starbound
Light platforming and combat, generous margins
The Lord of the Rings: Return to Moria
Stamina-based melee needs modest timing and positioning.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Starbound
Procedural NPCs follow simple fixed behaviours
The Lord of the Rings: Return to Moria
Orc hordes are scripted spawns, not adaptive minds.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Starbound
Procedural planets and loot keep early exploration unknown
The Lord of the Rings: Return to Moria
Procedurally generated mines hide ore, dangers and routes.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Starbound
Gear tiers, farming, and progression routes dominate
The Lord of the Rings: Return to Moria
Base building, gear tiers and resource chains decide survival.
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.