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
Remake of Gaiden with dual protagonists and explorable dungeons.

Optimization · Systems & Chaos
A lighter loot ARPG of frontier adventurers with class relics and buildable forts.
Fire Emblem Echoes: Shadows of Valentia leans Optimization (Pure Optimization); Torchlight III leans Optimization (Systems & Chaos).
Torchlight III leans a little harder on execution, though the gap is small.
Fire Emblem Echoes: Shadows of Valentia
Turn-based menus only
Torchlight III
Simple skill rotation and dodging
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Fire Emblem Echoes: Shadows of Valentia
Scripted enemies on both routes
Torchlight III
Monsters are scripted fodder
Torchlight III leans a little harder on variance, though the gap is small.
Fire Emblem Echoes: Shadows of Valentia
Hit RNG plus dungeon encounters
Torchlight III
Loot and map randomness standard for genre
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Fire Emblem Echoes: Shadows of Valentia
Dual-army routing and class promotions
Torchlight III
Relic and skill builds, fort crafting bonuses
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.