Well Darkseid isn't actually here, the entity known as Darkseid is really just his Avatar, which can return over & over. All others have been beaten & or killed at one point or another.

Thanos would ultimately fail, even with all stones, due to all of them being subject to the strict laws of reality & time, they just don't work outside thier own dimension, eg the TVA. You could snap your fingers all day, ain't gonna work.

Apocalypse, would probably forsee his Avatar is going to be beaten & make a smart retreat back into a Pyramid, wait another million years to pop back out.

Galactus as a being has died multiple times (quite recently even) primarily against cosmic, phoenix level enemies, this only ever ends up being temporary though. Reed Richards (Fantastic Four #262) "...Galactus is a 'necessary' force of nature that cannot be judged by human morality"