I’ve got a solis hybrid inverter with 48v dc coupled batteries. I had botched some code to read the inverter registers but then someone else wrote a really good integration for home assistant. It can read out all the power info from the inverter and can even can control some inverter settings.

Unfortunately the myenergi api doesn’t allow for sending data otherwise it consuls all be done in software.

Your solution is a great workaround to send info to the system. I have a lot of work on currently but am going to look into the variable ac signal control some more. Im hopeing someone makes an ic designed for the task. I found a digital potentiometer on RS that can deal with AC up to 12.5V (MCP 4551)

The only issue is the current limit is really low, 2.5mA so out of range from what you found for the ct clamps.