Both my home assistant emulated hue and my tasmota devices that had WeMo emulation stopped working last week with alexa. Found a solution buried in a github comment.
This addon works great: GitHub - t0bst4r/home-assistant-matter-hub: Publish your Home-Assistant Instance using Matter.
You install this, go into alexa app and configure a matter hub. Then add a “label” for each device like “switch.fireplace” and search for matter devices in alexa app. Works way quicker than emulated hue ever did.
I’m not developer, but this deserves a link on the almost defunct emulated hue integration. I read old devices should keep working with emulated hue, but new ones cannot be added due to now requiring SSL. Not sure why all of mine died last week.