@matchaman normally at a flee market you could find some in decent condition for like 5$ each and the kit is like 20$ so 25$ for a wireless OG controller would be the best but for me when i play my console games on my Pi i use the SN30 Pro and Pro+ but when i am on my Switch i use the official one they offer when you have the Nintendo online service (which i have not tested on my Pi yet).
I have recently started using 4-player games on the SNES emulator. I can tell you that I had to install and use lr-snes to get it working right. When I would try to use lr-snes9x2010 the player 2 controller would simultaneously move players 2 - 4 at the same time.
As quicksilver said, the best way to handle it is to save overrides for the specific games. I also saved the alternate emulator as the default for those games only. I have successfully gotten 4P to work on Super Bomberman 1 and 2, NBA Jam and NBA Jam TE for the SNES.
I have a similar behavior with the most recent version of Retropie running on my pi 3 B+. My Logitech F710 controller runs very well inside the Emulationstation, however if I start a games - regardless with kind of emulation - the controller stops to work.
@Halvhjearne My preferred method is indeed to preserve the original hardware so that changes can always be undone.
Maybe there is another way. I did managed to mod 2 original gameboy advance with ags-101 lcd mod and custom made micro usb charging lithium battery option without destroying the original shell. I think i will buy 2 SNES USB adapters to begin with and then i can always look on the internet after other options as well and they are pretty cheap on ebay.
@lostless@Newellj79 you are correct, but Mortal Kombat and just about everything else the 2 buttons at once either stops any directions from happening or stays with the first pressed direction. I think you guys are right i am downloading a fresh image now and hopefully i will be okay.