A few other manufacturers offer the provision for a three pin socket outlet inside the car.
Which is handy for charging a lap top etc.
I think the small Honda EV has this facility?.
MG have decided to discharge via the charging port, which makes sense as it can carry 2 kw’s +.
Some owners have even managed to exceed this discharge figure with a modification to the V2L adaptor.
Pulling north of 2 kw’s is via a three pin plug will create some heat at the plug of course.
Could one be added inside of the car, is what you are asking I think ?.
I guess it’s possible, but a small inverter powered from the 12 socket would do this…… maybe ??.