Against which factions is it easier for demons to fight, and against which is it more difficult?

Why not try other Inferno heroes against Wing? Maybe someone you wouldn't expect at first can easily defeat him? Variety might lead to something.
All of this is just my personal rambling.

Well, try other heroes. For example, you can try to rush him; this is one of the possible options. But if it goes into the late game, only Nimue is effective. And you won't defeat him easily, don't even dream of it. This Wing has long been declared a cheater, and in some competitions, he is even banned. Information about Elves as a race is scarce, and here we have their strongest hero.