For anyone that is interested,
Since the VenusOS betas support zero feed-in/dynamic power limiting on more inverters, including the standardized sunspec specifications..
I decided to try writing a ModbusTCP Sunspec bridge that talks to ESPHome.
A bit like this project: GitHub - izak/sunspecbridge: Simple ESP32 implementation for making popular PV-inverters SunSpec compatible, but instead of running on an esp32 chip, it connects to an existing ESPHome device.
I’ve only implemented and tested my own solis (single-phase) inverter.
But it may be useful for someone else.
You can find my project on github: GitHub - Menollo/esphome2sunspec: ModbusTCP bridge that connects to ESPHome and serves values via the Sunspec standard