I was able to accomplish this using dashcast and the trusted networks for my internal network. Dashcast basically just launches the HA site on the Google Home hub. The colors are a bit broken (Some white parts are black and you can’t see everything) but it is possible to choose trusted networks, then a specific user and get logged in. I also integrated it with iftt so I can say “Hey google, control panel” (or whatever you want to call it) and it launches a specific page in my Lovelace UI. (ifft triggers a webhook to call the dashcast script, which launches HA interface on the hub).
I was also toying with getting it working on a chromecast for my TV for monitoring temperature/multiple cameras at once but it is slightly trickier since their is no way to interact with it like the Google Home Hub. I think with nginx and some headers for authentication (for internal network use only) it is probably possible but I have not had time to figure that out yet.
Will try to post a video later today. The UI in my HA isn’t quite up to snuff but maybe just showing it is possible is interesting.
Edit: I also use https://github.com/skorokithakis/catt/blob/master/README.rst to accomplish the casting a specific site (uses dashcast under the covers I guess). I’m running HA in a python virtual env so I’m not sure how difficult it would be to accomplish this with hass.io or other installation variations.