deskthority

Looks like $8 controller (BGA only, so MOQ applies because PCBA required) + $4 coil gets you wireless charging.
Question is - will there be any interest in that?

+$12 to your Bluetooth controller = Qi charging? I’d consider that interesting! Though I’d be wary of case design and coil placement for charging geometry.

Yeah, this is more of "design the whole keyboard" territory. Also people knowing china say that qi receiver with 5V output costs about $1. So there's that.

There are flat coils with usb-c and -micro adapters going for a couple bucks retail in the Middle Kingdom. My guess is any bog-standard charge controller would work with them. The benefit would be being able to position them anywhere, flat against the case.