@lackyluuk, in 4.1 RB is prepared for waveshare 3.2 and 3.5 support (overlays and config in recalbox.conf) using fbcp program. It is really easy to make these

Geekwrom HD 3.5 Inch TFT Display Shield 800x480 is also supported see wiki page here https://github.com/recalbox/recalbox-os/wiki/Mini-How-To-(EN) in audio video section