I have a DC coupled and AC coupled system with sunways inverters in the AC that are connected to the same busbar as the AC1 output of the quattros. I have followed the factor 1.0 rule.
The system is off-grid and 60 Hz.
You program the ess assistant for frequency control. This is done with ve config.
It will only work offgrid since the system cant frequency shift the grid. Unless there are modbus controls over the pv inverter grid connected will not be an option for zero export.