The casino I play at is pretty splashy with a lot of guys opening with pretty wide ranges that are not GTO approved. I exploit them when I can, but it is hard against an entire table of them.

With that background info, my question is can I play offsuit connectors down to like 54o or 65o against a MP raise when I have position on them just to play more hands in which I think I can flop some equity, or should I continue to play tight and wait for them to pay me off (which is usually how I make money in those games)?

It is losing money. Even cold calling suited connectors is often a losing play. On the button facing a raiser a mix of calling and 3betting suited connectors can be okay though. Same on the BB.
Yes.

If you aren't already doing this, throw in more light 3bets to isolate things heads up or take down pots pre.

I'll often 3 bet hands like K9s-K6s or A7s-A5s to induce folds or make an easy fold myself if I get 4 bet. That's just part of my 3 betting range, but I do it to balance it. You are saying I should also think about 3 betting suited connectors such as 98s and 87s for the same affect?

Do not call raises with 54o. Permanently erase that thought from your memory.

I do at times. I stay away from 98, 109 etc but really love the 45o. Vs a table of calling stations or maniacs I will overcall this if the villains have 150bb plus. Less than that or if you are viewed as a nit and its not really worth it. You need to hit a big hand for all the folding you are going to be doing with bottom and middle pair, and especially against short stacks under 100bb I turbo muck. But vs the right villains, 45o, my favrorite hand, is great to play.

It sounds like you have the right table to experiment with. Vs guys that fold to 3bs, I will 3b 45o if we are over 200bb deep sometimes. Its so disguised when you hit you can usually win a huge pot.

Yeah, sometimes 3betting them at least. 76s and 65s are the best ones imo. 98s runs into trouble the way it interacts with suited broadways (get straight over straight, flop some draw when villain had a set, or flop a draw where villain has your outs and is ahead, etc).

Generally I think sticking to preflop charts is the way to go. Preflop charts have plenty of 3betting AXs, KXs, suited connectors.

There is just no really good reason to be in the hand with offsuit connectors unless it is heads up vs a small raise and you are closing the action in the straddle or big blind. With suited connectors you can flop straights, flushes, or straight draws or dlush draw. There are more backdoors you can pick up on turns where you can keep barreling. With offsuit connectors, you have a whole lot less going on. And sometimes you will be on a straight draw and someone will be on a flush draw that has you in bad shape.

There are 3 offsuit connector combos for every 1 suited connector combo, and those suited connectors often mix in folding preflop. They are nice to have for board coverage and to be sneaky at lower frequency, although a ton of times they don't flop well and there isn't much to do with them. Now add 3 times as many offsuit connectors that flop even worse and your range is going to just contain too much garbage on so many boards. AKA a bad, loose, rec range. It is bad for a reason.

In your first reply, you also said that calling with suited connectors is often a losing play as well. Should I be 3 betting them every time to isolate the the preflop raiser as well if they're loose and folding it if it's a tight nit in EP?

Calling with suited connectors can be fine in the right circumstances if you are also calling with stronger hands than that. The deeper you are and the worse your opponents are the more you should be sometimes experimenting with calling or 3betting these hands. Say you have 45s on the button and five extremely loose players enter the pot before you for 5x pot to say $10 in a 1/2 game. If you are 150bb deep this is a fine spot to call and see a flop. If the same five players are tight and fold to 3bs, this is a fine spot 150bb deep to 3b occasionally. If the same players are excellent players and you are just starting out playing live poker, folding is fine. If the stacks of the worst two players in the hand are under $200 folding is probably best. There are so many variables to consider.

Guy on YouTube, Alvin Teaches Poker has a great video or four about how we should be playing in position as wide as possible to then dial back how out of control wide you are to find your sweet spot. He is also a massive advocate of only 3b or folding for the most part. Bart Hanson also has hundreds of fantastic videos explaining the merits of overcalling on the button with hands like this. Both guys are very good players from what I understand.

For your specific question some questions I might ask myself at some point during the session to determine what type of range I was going to adapt to the game that day. Also listed close to in order of importance

1. How deep are my oppponents
2. How bad or good are they
3. Am I in posiion or will someone enter the pot behind me?
4. Can I get the pot heads up or take it down vs these players with a 3b?
5. Are they loose postflop?
6. Are they aggressive postflop where I cant normally realize all my equity or are they passive and my equity is easy to cheaply realize?
7. If they are passive are they calling stations also? Because I want to be in as many hands as possible with these players similar to what Alvin Teaches Poker suggests
8. What is my image at the table? Do they look at my 3bs as weak, strong, or in between? Do they look at my calls as weak or they are unsure of what kinds of hands I am calling with?
9. Do I have my opponents ranged well and are they ABC postflop?

I dont play these hands close to 100% of the time even in position. I would guess I fold suited connectors 1/2 to 3/4 of the time and unsuited connectors 9/10 or more. Playing most suited connectors from the button in some way if stacks are deep enough.

I would look at preflop charts. Sometimes fold, sometimes 3bet. Call more of course in BB getting a price, calling on button sometimes and sometimes 3betting. Mostly folding these hands in all other positions. And after there are cold callers, they are even more of a fold.

If the initial open raiser folds a fair amount to 3bets, then it is better. If they always peel it isn't really worth it. Like if someone has a limping range, but then they open raise a hand and never fold to 3bets, don't 3bet that guy light. But light is subjective. I still like 3betting hands like AQo, KTs+, ATs+, A5s basically always and would need a really compelling reason not to.