Can you trick a grid-tie inverter with an off-grid system?

Yes, you can trick a grid-tie inverter with an off-grid system, but it’s not that simple.

Can I use a microinverter to supplement an off-grid system?

You can easily use microinverters to supplement an off-grid system. If you are connecting it to an AC coupling capable system. I have a cheap 300W gti plugged into mine. Just wanted to see if it works. Also means I'm running AC thru 30m of cable instead of DC. Less voltage drop and simplifies the wiring.

How do you Spoof a grid-tie inverter?

There are ways to 'spoof' a grid-tie inverter to generate power even when the grid is down (usually a big no-no) and this can be achieved either through AC or DC coupling into an off-grid system. DC coupling doesn't seem to me to be a good idea because you'd be converting DC-to-AC (microinverter) to DC-to-AC (off-grid inverter).

Are grid tie inverters supposed to stop anti-islanding when off-grid?

The grid-tie inverters are supposed to be told to stop that anti-islanding stuff when off-grid. I've run mine with some grid-tie inverters that aren't converted for off-grid or backup operation. So long as batteries need charge, the grid tie inverter produces all it can and Sunny Island charges its batteries.

Does a sunny island battery inverter work with grid-tie inverters?

Systems built around the Sunny Island battery inverter/charger (my picture) work with grid-tie inverters and stuff the excess power into their battery. The grid-tie inverters are supposed to be told to stop that anti-islanding stuff when off-grid. I've run mine with some grid-tie inverters that aren't converted for off-grid or backup operation.

Do microinverters work if you live off-grid?

With the ability to do this consistently, microinverters eliminate exposure to high voltage DC electricity while powering your equipment or appliances. Since this is a relatively new technology, many folks aren’t aware of the way it works or its benefits when living off-grid.