head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is variance, and it is a single point.

Execution · Grand Arena
Hero shooter with team-up ability synergies.
Execution · Grand Arena
A hero shooter where teams brawl over objectives using locked ability kits.
Marvel Rivals leans Execution (Grand Arena); Overwatch 2 leans Execution (Grand Arena).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Marvel Rivals
Hero aim and ability timing
Overwatch 2
Aim and ability timing decide most duels.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Marvel Rivals
Team-fight cooldown trading is prediction
Overwatch 2
Adaptive enemy comp counters and ult baiting.
Marvel Rivals leans a little harder on variance, though the gap is small.
Marvel Rivals
Map and team comp roll affects
Overwatch 2
Minimal randomness, mostly map and matchmaking.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Marvel Rivals
Hero synergies and team-up combos deep
Overwatch 2
Comp building, ult economy, and cooldown tracking.
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.