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The Polycade software uses XInput (xbox) controls. Ideally, your cabinet uses controller boards that show up as XInput devices. Alternately, you might get good results with a 3rd party mapping software like Xpadder.
Do you already have a controller board? If so which one?
I believe the recent IPac devices work with XInput, and we've seen boards like this work well for cheap (you need 1 per player):
https://www.amazon.com/SJ-JX-Encoder-Controller-Android/dp/B07GJK2G1F/ref=sr_1_17?dchild=1&keywords=arcade%2Bstick%2Bpcb&qid=1607487953&sr=8-17&th=1
You could also go with a Brook Ultimate Fight Board if you're not on a budget, but that's usually overkill for an arcade cab. Aside from being an overall quality board, one advantage of the UFB is that you can switch your joysticks between D-pad / Left Stick / Right Stick, allowing you to play games that are exclusively mapped to only one input.