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
Linear JRPG built around real-time paradigm switching and stagger combat.

Optimization · Pure Optimization
Methodical dungeon mapping and puzzle-solving with token real-time combat.
Final Fantasy XIII leans Optimization (Pure Optimization); Stonekeep leans Optimization (Pure Optimization).
Stonekeep leans a little harder on execution, though the gap is small.
Final Fantasy XIII
Paradigm shifts need timely menu reactions
Stonekeep
Real-time mouse swings need only basic timing
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Final Fantasy XIII
Scripted stagger-phase bosses
Stonekeep
Dungeon denizens follow fixed scripts
Stonekeep leans a little harder on variance, though the gap is small.
Final Fantasy XIII
Minor randomness in enemy actions
Stonekeep
Unmapped corridors and secrets are scripted-but-unknown
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Final Fantasy XIII
Paradigm sequencing and stagger timing are solvable
Stonekeep
Mapping, rune magic and inventory puzzles are the real test
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.