It recently realized that the new inverters with a smart load/aux output need a changeover to control all 3 outputs. BTW. Why do they call it an Aux output? It sounds like something on a Hi-Fi or VCR
You now have an Eskom Load, an Inverter Load, and an Aux Load. Using a 3-phase changeover is the only product on the market that can work as far as I know.
The Aux output won't work when the Inverter is not working and also the Inverter load won't work, so both these loads need to be switched to Eskom in the event the Inverter fails or is switched off for maintenance.
You will have three main breakers, one for each feed, three earth leakages, one for each feed, and the various breakers for each feed.
Just make sure the labeling is in place and not too confusing