Thanks, the wikipedia explains anti-islanding, in the case of "microgrid" or "level 3 hybrid" inverters, they allow you to island so that if the grid goes down your panels can continue to power your home, why do so few inverters support this, complexity, compliance?
Is it possible to put a gizmo between the grid and your old "anti-islanding" inverter to replicate what the new hybrid inverters are doing to save you replacing a perfectly fine inverter just to get microgrid?
Could the gizmo "pass through" voltage, frequency and phase to the old inverter when the grid was up, if the grid goes down the gizmo detects this and disconnects from the grid and "spoofs" a voltage, frequency and phase to the old inverter, or you could just defeat or disable the anti-islanding on the old inverter?