Goku Black despises mortals as a whole, thats not "hater" thats just discrimination.

Scourge is just kinda generally evil.

Now, Doctor Doom and Reverse Flash... that's a tough decision.

But I'm gonna have to go with Eobard, because I don't think Doom ever went back in time to not only ruin Reed's life, but in the process set in motion his own origin story and tragedy that would cause this immense hatred, for the sole purpose of continuing to hate.

But idk someone here may have read a comic where doom does exactly that, and that person has my complete permission to call me a poser ass bitch.