Hi,
Just finished a work-around for running MakeCode Arcade games natively in RetroPie and from the Raspberry Pi OS text console, with keyboard and controller support for up to 2 players:
https://github.com/Vegz78/McAirpos
Not sure if this could be of interest here, meaning if it could work with/be integrated in a similar way into Recalbox?
Br,
Vegard