My goplug smart EVSE does not require internet, and you can set it to lock to a specific rate either with the phone or desktop app or DIP switches like dumb chargers. All brands I have seen will allow setting the rate, but I am not sure how good they are at "locking" to a rate (so they remember and always start at that rate after being unplugged, like mine does.) It might be good to start a list of those you found that require internet, or cannot lock to a rate setting.