I did a coreXY laser maxhine…
CoreXY Laser Engraver files on Printables.com
The downside here is that it’s a small size diode laser that I made it for. I think I am going to redesign for the NEJE A40640 though. Probably 10mm width belts too.
Of course that doesnt have auto-square, but once set uo, it’s been good because the coreXY system keeps it square unless Iet the frame move (and I don’t). I have provisions for end stops, but I’ve never actually installed them.
I think for yours, you could just use LR firmware and ignore the Z axis. Leave no end stops plugged in and it should home OK. Of course a smaller board, like an Uno CNC shield would be nice, since it has only the 3 drivers that you need. You could probably work up something using FluidNC on an ESP32 as well.