The wireless keyboards and touchpads have a Lightning-to-USB-A cord, which can be plugged into the computer directly. Primarily for charging, but if you charge off the computer it'll use the wire instead of Bluetooth for typing.

Do you know of any PC keyboards/mice that do this? I want to be able to do things in the BIOS so having a Bluetooth keyboard that charges and is functional over a mini USB adaptor would be really useful. Same with a mouse, Bluetooth is not always great but a mouse that did both wired and wireless would be neat.

Even if this is only used once every six months when something goes wrong it would be nice to have. I prefer to use the same keyboard/mouse combo for all machines. Just having that full flexibility helps.

I don't know about keyboards, but my wireless Logitech mice that charge over USB can be used plugged while charging.

All of them? At least every BT keyboard/mouse that I have used does this.

But the cable they provide to charge those is USB-A not USB-C.