Looks like you may have 2 Multiplus inverters operating in parallel or as part of a split phase system. These will both be shown as the device circled in Red.
The device circled in Green is the MPPT solar charger. This should also charge the main house bank. The other Voltage regulator drawn in would regulate the charge from the vehicle engine, also to the main bank.
The device you label as an auto-transformer should perhaps be an isolating transformer….??