It wouldn’t affect it at all, the transfer switch for transferring from utility power to car battery power would be located after the service disconnect or mete

It wouldn’t affect it at all, the transfer switch for transferring from utility power to car battery power would be located after the service disconnect or meter socket, power isn’t backfed into the grid, since the transfer switch has lockout provisions to prevent it. This is a solved problem, backup generators have been around for a while. Also, linesman assume that utility lines are hot.