Not sure if this is the right thread…
I’ve made a few footbar icon sets that show the correct button based on the SNES layout.
Just put the one you want into your theme into ~/skins/[THEME NAME]/sys.py/gameshell/footbar_icons/ and make sure it is named footbar.png.
Alternatively, if you don’t use a theme, you could put it into ~/launcher/skin/default/sys.py/gameshell/footbar_icons/ (although I assume this will be overwritten on OS update)
Here’s an album to see them betterer: https://imgur.com/a/8nU3ZTR