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.

Execution · Practiced Mastery
The original Souls game: scripted boss patterns you solve with builds, routes and disciplined execution.

Optimization · Practiced Mastery
Sandbox warfare testing directional combat skill atop an optimisable army and trade economy.
Demon's Souls leans Execution (Practiced Mastery); Mount & Blade leans Optimization (Practiced Mastery).
Demon's Souls leans a little harder on execution, though the gap is small.
Demon's Souls
Stamina-timed dodges and parries punish sloppy hands.
Mount & Blade
Directional blocking and couched-lance timing demand real skill
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Demon's Souls
Invasions exist but bosses are scripted patterns.
Mount & Blade
AI lords and battle tactics are mappable scripts
Mount & Blade leans a little harder on variance, though the gap is small.
Demon's Souls
World tendency and upgrade drops add mild noise.
Mount & Blade
World events, prices and tournaments shuffle each campaign
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Demon's Souls
Builds, routes and learned movesets are fully solvable.
Mount & Blade
Army composition, trade economy and fief management drive conquest
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.