In Gamesir Nexus app you can just set up the custom buttons as you see fit, oh and I use 2% inner deadzone for the sticks as setting to 0% can result in some idle drift in some games.
The top custom buttons for me are set to RTSS and game recording hotkeys, with shift layer enabled they function as show/hide RTSS and Steam stats overlays too.
The top custom buttons for me are set to RTSS and game recording hotkeys, with shift layer enabled they function as show/hide RTSS and Steam stats overlays too.