Cheapest I've seen these and they work for PC, Mac, PS3, and Switch...aside from the Genesis Mini. Limit of 3 per customer.
https://www.bestbuy.com/site/retro-bit-sega-genesis-6-button-arcade-pad-for-pc-mac-sega-genesis-mini-playstation-3-and-nintendo-switch-black/6361747.p?skuId=6361747