I just got this error trying to install Tekken 7:
wine: WINEARCH set to win64 but ‘/home/USERNAME/.local/share/lutris/runners/winesteam/prefix64’ is a 32-bit installation
So, somewhere during my winesteam installations (all via scripts), some game must have used prefix64 and winearch=win32.
Either that or the wineSteam runner automatically installs in winearch win32 by mistake.
EDIT: just checked, everything is being installed in the 64 bit prefix, although some really old dx9 games with no 64-bit clients are present there… Even games that require some 32bit winetricks