Reminds me of the KSP2 fiasco. Management insisting on reusing the engine from the old game, and firing all the senior devs who could have told them there was no possibility of getting the features they’d announced to work without rewriting the engine from scratch.
Leave the grid out of it. Your PV’s charge your battery with DC, that gets used as DC by the USB-PD outlets in your wall. And you have an AC-DC converter for when you need to consume grid power.