head to head
Neither is simply harder - they are hard in different places. Borderlands 2 demands more execution; Space Crusade demands more reads.

Optimization · Systems & Chaos
Loot-shooter RPG built on gear chasing.

Optimization · Systems & Chaos
Turn-based squad tactics managing dice odds and positioning in 40K corridors.
Borderlands 2 leans Optimization (Systems & Chaos); Space Crusade leans Optimization (Systems & Chaos).
Borderlands 2 leans clearly harder on execution.
Borderlands 2
Aim matters but generous hit feel
Space Crusade
Turn-based - no twitch demands at all
Space Crusade leans clearly harder on reads.
Borderlands 2
Enemies are scripted loot fodder
Space Crusade
Multiplayer rewards limited reading of opponent moves
Borderlands 2 leans a little harder on variance, though the gap is small.
Borderlands 2
Procedurally generated weapon drops vary
Space Crusade
Dice rolls drive combat outcomes significantly
Borderlands 2 leans a little harder on optimization, though the gap is small.
Borderlands 2
Skill trees and gear math heavily solved
Space Crusade
Squad composition, positioning and mission tactics are the core
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.