head to head
Neither is simply harder - they are hard in different places. Street Fighter V demands more reads; Warcraft III: Reign of Chaos demands more variance.

Reads · Grand Arena
A reads-heavy neutral game where V-System decisions and opponent modelling decide bouts.

Optimization · Grand Arena
Blizzard's hero-centric RTS where build-order theory meets surgical unit micro against humans.
Street Fighter V leans Reads (Grand Arena); Warcraft III: Reign of Chaos leans Optimization (Grand Arena).
Street Fighter V leans a little harder on execution, though the gap is small.
Street Fighter V
V-Trigger combos and meaty setups require solid execution
Warcraft III: Reign of Chaos
Micro of heroes and units decides fights
Street Fighter V leans clearly harder on reads.
Street Fighter V
V-System neutral game heavily rewards opponent habit exploitation
Warcraft III: Reign of Chaos
Scouting and out-guessing a human opponent's tech
Warcraft III: Reign of Chaos leans clearly harder on variance.
Street Fighter V
No RNG; match flow is entirely player-driven
Warcraft III: Reign of Chaos
Creep routes and item drops add randomness
Warcraft III: Reign of Chaos leans clearly harder on optimization.
Street Fighter V
Season-by-season tier lists and V-Skill routing reward study
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.