Is there a way to go back to splore list using a gamepad? I'm using a raspberry pi to play games. But it's annoying to plug a keyboard just to go back to game list.

Does "Start" or the equivalent on your gamepad bring up a popup menu? It does on a PC, and there should be an "Exit to Splore" option in that menu.

No, it doesn't. That's the problem. There's no button to exit game (at least button mapped as "start" doesn't bring the popup menu).

You probably need to look into configuring your gamepad on Raspi so start btn = ENTER (pause). Then you can exit to splore from the pause menu.