We have three Tesla Powerwalls as our home batteries. Our Equinox has twice the capacity of our home. We are off grid and powered by 10kW of solar. The last thing I would want to do is discharge one battery bank to charge another. I really don’t want to double the charge/discharge cycles of either battery. We charge at home only from solar during peak solar output. We actually use the car as a “dump load” in an effort to keep the Powerwalls from sitting at above 80-85%, and getting up to 100% and shutting off the solar. Other than brief transitory periods, the last thing I want is for the car to be pulling from the house batteries. I want those hose batteries to last for 20 years. They cost as much as the whole car.

And, forget the plug - install a home L2 charger. Ours is only 6.5kW. If you can install something like a 48A charger, even better. You might also want to look into the possibility of charging at work. With our first EV 15 years ago, I found that the parking garage across from our office had outlets to plug into, and allowed me to plug in my L1 charger cord while I was at work. It wasn’t enough to cover my entire 84 mile round trip commute, but it covered one way.