I think generally speaking you can send the touch signals over the eDP connection, but I'm not sure that still works with higher resolution displays that require more bandwidth 🤔
I've not opened up this laptop (Dell l7400 with touchscreen) as it's a work device, but I imagine there'll probably be two separate cables coming out of the screen section, one of which connects as a peripheral device (i.e. the touchscreen)
@Nzall It might also never become available... I really like touchscreens during travel, would like to make sure whichever device I get has that out of the box :)