Which used Kia Soul EV hatchback should I buy?
With First Edition and Maxx being essentially the same, it doesn't really matter which version you pick. That being said, as First Edition cars came out sooner, these will likely outnumber Maxx cars for a while on the used market. And with just the one battery size available, there isn't any more choice there either.
However, with all versions very well equipped, and having great performance and range capabilities, that lack of choice really isn't an issue.