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 · Grand Arena
Build-fight battle royale with deep mechanics.

Execution · Competitive PvP
Turn-based artillery comedy where teams of worms annihilate each other.
Fortnite leans Execution (Grand Arena); Worms 2 leans Execution (Competitive PvP).
Fortnite leans a little harder on execution, though the gap is small.
Fortnite
Build-edit-aim combos punish slow hands
Worms 2
Ninja rope mastery and pixel-perfect grenade arcs win games.
Fortnite leans a little harder on reads, though the gap is small.
Fortnite
Box fights are pure adaptive mind games
Worms 2
Human opponents bait positions and hide intentions.
Fortnite leans a little harder on variance, though the gap is small.
Fortnite
Loot drops, storm, item rotations vary
Worms 2
Wind, crate drops and terrain randomness swing turns.
Fortnite leans a little harder on optimization, though the gap is small.
Fortnite
Loadouts, mats economy, rotations solvable
Worms 2
Weapon economy and positioning theory are studyable.
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.