The Pokken controller is a great option, and is not very expensive.
On Retroarch I use the Pokken Controller that came out for Nintendo Switch and Wii U. It’s an awesome controller made by Hori I believe. Same layout as SNES but more comfortable and two extra buttons that can be programmed for save states. It’s got a nice long USB cord.
https://www.amazon.com/Nintendo-Tournament-Controller-Officially-Licensed-Pokemon/dp/B01A6LEXFK
Try the official Pokken Controller (works on PC and Switch). I seriously believe it's the d-pad.Ps: stay away from 8-bit do, I tried almost of their crap controllers. The Hori Fighting is also good, but I largely prefer the Pokken one. With Xbox is false diagonals' party.