Thanks for taking the time to reply. I’m sorry I wasn’t clear enough in my question. Other replies have seemed to understand what I was getting at. The only reason I mentioned the PHEV Niros was because I was trying to provide a backstory for how I ended up with an EV6 in my garage on loan, and also so nobody would wonder why I had two Wallbox stations in power sharing mode. I guess I could have simplified the whole thing by not mentioning the PHEVs and the dual EVSE stations, especially since none of the really good replies are pointing to the power sharing setup as a potential cause.
One other thing another commenter mentioned that I think bears repeating here for posterity is that the EV6’s OBC is not limiting voltage input and the 10.9kW rating on it has probably more to do with the difference between the North American commercial, North American residential, Korean, and European nominal voltages which range from 208-240. At 48A, the 10.9kW number is a lot closer to the 220V standard in Korea than the 240V my house gets.