Sorry, what device are you using to supply power once you've flipped the switch? Sure, you can get a (legal, even) manual transfer switch and plug in a little portable generator, but if we're talking about using your car as a power source, this is not going to work.
I previously used a portable propane generator for a 30amp inlet to transfer switch. In my test runs it didn’t go that high.
Today I could plug in a car that gives off 20amp into the same inlet, it would limit how much load it can carry, but I could stay below 2.4 kw if needed. Why wouldn’t that work?