Yes I work in automotive and have routinely replaced ECUs. I work for an American OEM, I guess we don’t pair ecus to each vehicle. Unless its ecm/tcm/radio/security gateway and probably the key fob ecu. Everything else is just a part number that you can easily swap out. The few screws holding the controller and the wiring connector(assuming the controller is easily accessible)… Though I own an Audi and use VCDS I was not familiar with pairing an ecu to the vehicle, however I was aware of coding in the VCDS. (I have not yet needed to swap an ecu on my car)