head to head
Warcraft III: Reign of Chaos asks more than FIFA 20, and the gap is optimization.

Execution · Grand Arena
A football sim where reading opponents and precise execution both decide matches.

Optimization · Grand Arena
Blizzard's hero-centric RTS where build-order theory meets surgical unit micro against humans.
FIFA 20 leans Execution (Grand Arena); Warcraft III: Reign of Chaos leans Optimization (Grand Arena).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
FIFA 20
precise passing, dribbling, and shot timing
Warcraft III: Reign of Chaos
Micro of heroes and units decides fights
Warcraft III: Reign of Chaos leans a little harder on reads, though the gap is small.
FIFA 20
reading human opponent tactics live
Warcraft III: Reign of Chaos
Scouting and out-guessing a human opponent's tech
Warcraft III: Reign of Chaos leans a little harder on variance, though the gap is small.
FIFA 20
minor ball physics and injury randomness
Warcraft III: Reign of Chaos
Creep routes and item drops add randomness
Warcraft III: Reign of Chaos leans clearly harder on optimization.
FIFA 20
formations and player builds solvable
Warcraft III: Reign of Chaos
Build orders, creeping routes, and matchup theory run deep
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.