I very much doubt it, as it won't fit for starters. There was no precedent for Toyota to design it to be compatible with the previous generation car, and a lot has changed.
no, it has not been done yet. just yanking it out will be a much bigger job than the lift back. and you are dealing with lithium, so the battery threads here may not apply altogether. how many miles on her? see this thread by member @gallde 'PIP EV range falloff'.
Looking forward more details about battery and if they are available for sale then kindly mention the price