Hello
if you have recalbox 4.0.2
edit /boot/cmdline.txt
and add at the end of line this :
usbhid.quirks=0x0079:0x0006:0x040
like this :
dwc_otg.lpm_enable=0 console=tty3 loglevel=3 elevator=deadline vt.global_cursor_default=0 logo.nologo root=/dev/mmcblk0p7 rootwait fastboot noswap usbhid.quirks=0x0079:0x0006:0x040
save and reboot your raspberry.
Go to Emulationstation Menu > options gamepad.
Configure only player 1