The diode idea was to have the panels run the fridge and charge the batteries.
But if the panels can't power the freezer by itself, that won't work.
There are also some folks on utube that have panels dedicated to just their freezer.
Because there is so much loss when you start including batteries.
He's right.
You can hook a relay to the normal, turns-on-at-night type switch.
So when the switch turns on, it turns off power to the inverter.
Or turns off power from the inverter.
Same problem with temp switches.
They commonly turn on when it's cold and off when the heater is warmed up.
Hard to get the common adjustable temperature switches to turn on the fan to a solar heat box
if they turn off when it gets hot.
So I rigged a relay to invert the output.