Support for it exists in the python Broadlink library here python-broadlink/broadlink/switch.py at 730853e5faf2cf979596662faf9def2b1f8fee6d · mjg59/python-broadlink · GitHub if that helps - it’s fairly similar file structure to the Broadlink integration core/homeassistant/components/broadlink at dev · home-assistant/core · GitHub
The home assistant integration is based on that library, so I am not sure why that device is not working.
Unless I’m missing something ehc31 isn’t mentioned anywhere in the home assistant broadlink package
It seems from the source that is an instance of the bg1.