I recently installed an EcoFlow smart panel to keep certain circuits alive during a grid outage. In the main panel, there is a circuit for each light or set of lights per room within the main residence. What I would like to do is, during an outage, these multiple circuits would instead become one circuit. The benefit of doing this is that I won't need to use up multiple relays in the EcoFlow panel, since one 15A circuit can easily handle all the lights.
To this this, I envisioned adding an additional panel that contains a terminal bus bar. This bus would be fed from a separate breaker in a dedicated breaker box for the smart panel, which is then fed from a relay in the smart panel. To ensure separation of the circuits and to prevent backflow to the relay when on grid power, I'd use a schottky diode on each terminal. From here, I'd use wire nuts to connect the leads from each lighting circuit to their respective breaker in the main panel and the smart panel breaker box.
Would this work?