Way too much flow. 1 Koralia 1 and an eheim would turn a 75P into a whirlpool. You want to do 2x that. You wouldn't be able to keep rocks down, let alone plants lol
The 75P is pretty easy to get sufficient flow in, as it's not terribly long. I put a koralia 1 in my tank when my xp3 started to slow down and it mowed everything down. Even the koralia nano is a it too much. If you go with two eheims you won't need ANY powerheads, ever.
Remember, I've had a 75P for almost 2 years now