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
Co-op zombie shooter with adaptive AI Director.

Execution · Practiced Mastery
Co-op melee horde shooter with deep builds.
Left 4 Dead 2 leans Execution (Practiced Mastery); Warhammer: Vermintide 2 leans Execution (Practiced Mastery).
Warhammer: Vermintide 2 leans a little harder on execution, though the gap is small.
Left 4 Dead 2
Headshots under horde pressure need aim
Warhammer: Vermintide 2
Melee timing, dodges, headshots demanding
Left 4 Dead 2 leans a little harder on reads, though the gap is small.
Left 4 Dead 2
Versus special-infected ambushes have reads
Warhammer: Vermintide 2
Specials are scripted, not adaptive
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Left 4 Dead 2
AI Director randomizes spawns and items
Warhammer: Vermintide 2
Director spawns and loot randomize runs
Warhammer: Vermintide 2 leans a little harder on optimization, though the gap is small.
Left 4 Dead 2
Route knowledge and weapon picks solvable
Warhammer: Vermintide 2
Builds, talents, weapon breakpoints solvable
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.