@sugo98 I ran into this same issue. After 3 hours of head-banging, I managed to solve this, thanks to your post that gave me a hint: 5th joystick.
For some reason, this game wants the Slot 2 to be plugged in. So it actually requires 5 players, the 5th one being in fact the Player 2. So you just need to tell RetroArch that Port 5 is controlled by the same gamepad as Port 4. Make sure this 5th player is set to a PlayStation controller or analog pad and it works.
This seems to be the same behaviour among all KCET football games. And maybe Track 'n field games too?
I hope it'll help you.