We use the USB connection between PC and USB to inject the payload. As we know, Arduino (or Teensy) can be used to simulate USB-HID inputs to Switch. USB-HID is drastically different from things we use here, but Arduino still uses USB-Serial to transfer data through USB even when not used in USB-HID mode. The question is, can we in theory use Arduino (or similar boards) with USB-OTG to inject the payload into Switch? If so, can we use Arduino's GND to shorten Pin 10 or there's some sort of galvanic isolation between the Switch and Joy-Cons involved? Thanks.