ZOOM flushdraw + 2 overcards in a 3way 3bet pot

I don't play zoom or rush so don't hold me to it.

1) Should one 4bet preflop?
For value or bluff? The CO calling kinda changes my mind to a call, but I am not sure. I 4bet this but it's the same as the flop, I am not happy getting it in.

2) What is the best line to take on the flop?
We know MP doesn't have a set and neither does the CO. I don't like calling, the turn bricks and then we stuck scratching our heads what to do when he fires again. When we called pre we wanted a flop similar to this right? I get it in.
*Going to edit this to MP might not have a set?

Considering their range includes pairs, str8 and sets only, no draws: 99-KK,66,33-44,75s,52s,75o,52o,7s5s,5s2s you are:
40% vs 1

If we remove the str8, given the PF action: 99-KK,66,33-44,
45% vs 1

If we consider only sets:66,33-44:
25% vs 1

I cannot run away from pushing in this spot.

66,33-44,75s,52s,75o,52o,7s5s,5s2s

I was thinking it would be a lot tighter than this, vs UTG. I might be missing out by not considering this or even doing this. Is this how it is playing zoom? I was thinking 77+ and 98s, T9s, JTs, QJs, KJs, KQs, AQs, AKs, etc
But I am very used to seeing straight forward play, especially in 3bet pots.
My poker brain needs a upgrade.

Hello,

I think the first thing would be to understand why you call with AKs pf.
I see it well, my arguments are that
We dominate his 3bet range from Ax,
Range of 3bet vs UTG is tight, we won't have as much FE with 4bet.
When you hit a draw on the flop, it will be very strong, to the nuts and you will dominate other draws.
The times you have a draw you can count the implied K and A against hands like TT-QQ, KK.

This is the case, you have a push flop, against his top range (KK+, set) you are fair, but against 88-QQ and bottom FD you have a lot of equity.

Honestly, I don't think it is much seen, but as I was building a worst case scenario, thought about including them.

I think the more realistic would be the second one: 99-KK,66,33-44
Not sure if QQ and KK should be included, but also could include 77,88. Overall, I think that's the range equivalent, thus 45%.
Probably should include other FDs, but as hero is blocking A and K I am not sure. If we include that, equity will be higher and again, I was "mathing" against top range.