We use a counter top oven (toaster oven) with a convection fan multiple times a day. It probably suffices for a legitimate 80% of our re-heating or light cooking needs.
I believe it’s somewhere in the range of 1600-2000 watts, but I’m not sure.
But it is DEFINITELY, beyond any doubt, faster than any kind of conventional electric oven or split-oven, just be TSA you said, less volume to heat up.
If your battery storage bank can handle a conventional oven, then it will definitely handle a countertop oven.