FrothByte
Nailcutter Massacre
To be honest, I don't see how the fodder army will take out Vision and Thor (and Superman if he's included). Vision because nothing the fodder army has can break through his vibranium skin plus he can just become intangible if things get rough. His mind-gem blasts should be able to tear through anything and anyone in the fodder army.
As for Thor, to be honest if he had enough time he could probably have soloed that entire Outrider army (minus Black Order). The lightning coating he used at the end of Ragnarok should make it extremely difficult for any of the fodder to close in on him other than the leviathans, but he's also shown that he can take out multiple leviathans before... and that was without Stormbreaker. The only issue for him would be his endurance, though since I don't recall Thor ever getting tired (we saw him injured but not tired) I'm not going to assume to know his limits.
Superman... well, his combination of super speed, strength and durability should make it near impossible for the fodder army to land significant damage on him. The only issue is his endurance, same with Thor, but as long as the sun is out there I'm pretty sure he'll just keep on going.
But other than those 3, the rest of the heroes die. Pretty horribly too. The parademons were strong enough to chew up Steppenwolf, and that means they can chew up everyone else other than the above 3 mentioned and probably Hulk, but then we know Hulk can get overwhelmed by the Chitauri gliders. The others put up a fight but in the end die of exhaustion. There's just too many fodder.
That said, the heroes do eventually win due to the 3 I mentioned above.