I have heard of proof of concept camping trailers that not only have batteries but also motors in the wheels so the can provide extra power when you drive (restoring the range you loose when towing) and also regen braking. Not low tech, but would be really useful https://www.greencarreports.com/news/1133124_towing-with-an-...

Will any electric car let you drive while it's plugged in?

I'm pretty sure Tesla's Rivians get locked into park when the charger is connected.

I think you're correct, my Fiat certainly doesn't. That is, however a firmware update away provided the type2 or CCS protocol can distinguish between a mobile or static charger, or be extended to do so. My OP was a slightly off the cuff post to highlight the use of a trailer for say cheap city cars, rather than a removable battery.

> Will any electric car let you drive while it's plugged in?

That’s what I was wondering too. Like you, I’m pretty sure the major EVs don’t let you drive while charge, but I haven’t actually tried it.

No, even my PHEV doesn't let you drive while plugged in.