This blueprint and these instructions will help you setup your Fusion Energy Smart Home Smart Home Energy Monitor (also known as sem-meter) to work with Home Assistant.
The illustrated instructions are here: sem-meter-home-assistant/README.md at main · eyal0/sem-meter-home-assistant · GitHub
It uses a blueprint to setup MQTT and that blueprint is here: sem-meter-home-assistant/create_fusion_energy_smart_home_energy_monitor_devices.yaml at a2f2fd397e34800e1f4c8740b3706708a784fc07 · eyal0/sem-meter-home-assistant · GitHub
Happy to receive feedback about it, here or in github. I hope that this helps you.