Hi, I can't find any clear information on this... can I do power sharing (or load sharing) between a gen2 and gen3 wall connector? Or should I purchase a 2nd gen2 model instead?
The Gen3 doesn't even support load sharing yet (requires a firmware update). It is unlikely to be backwards compatible. No big advantages on the Gen3 yet. Maybe easier to install, smaller, etc.
Not just unlikely. Someone did ask that directly to Tesla, and they responded that they are not going to make the Gen3 ever be able to share with Gen2 units.
Gen 2 load sharing control is by the separate twisted pair cable between units. Gen 3 is via wifi when they enable it with the firmware update (for the WC, not the car) as mentioned above. So there’s no way it would ever work.
There was some glimmer of questioning at first, though, because inside the Gen3, there is a kind of unused ethernet port, and there was some theorizing that it could be enabled at some point to terminate that twisted pair on with a plug, and then the Gen3 could be master and send control signals to the Gen2s down the string, but it sounds like that's not in the plans.