If you bought the plane in the marketplace and are looking for the aircraft.cfg you’re probably outa luck because they encrypt them.
Otherwise, the directory for Steam is:
\SteamLibrary\steamapps\common\MicrosoftFlightSimulator\Official\Steam\carenado-aircraft-pc12
However, I know that some things, like the hanger info, is pulled from the aircraft.cfg file from the default livery. Maybe the same works for radio. I showed here how you can do that: