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

Execution · Grand Arena
A 2D platforming MOBA blending skillshots with live human mind games.

Optimization · Grand Arena
Diesel-punk CoH-style RTS with mechs and infantry cover.
Awesomenauts leans Execution (Grand Arena); Iron Harvest 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.
Awesomenauts
Platforming aim and skillshots reward dexterity.
Iron Harvest
squad micro and cover
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Awesomenauts
Human opponents adapt lanes and picks constantly.
Iron Harvest
MP flanks vs humans
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Awesomenauts
Small map and shop randomness.
Iron Harvest
fog of war
Iron Harvest leans a little harder on optimization, though the gap is small.
Awesomenauts
Builds, timings, and push economy solvable.
Iron Harvest
build orders and unit comps
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.