Google Cast app that adds custom overlay text over YouTube videos

I often invite my friends to watch YouTube musical video playlists on my big screen in my home. I use to cast the videos from my Samsung S7 (updated to Android 7.0) using Google Home to a Chromecast Ultra device, that output the video via HDMI to my big screen. Google Home is really good because it can cast YouTube in background while I can use the phone for other purposes too. Now MY NEED is to add an always-on custom overlay text on the botton of my big screen, like this "[login to view URL] - 24/2/2017". I would prefer a software solution that allows me to keep the existant chain of hw to cast the videos and that allows me to easily change the text a few times during the evening, from my phone. Can you create a software solution? (demo very appreciated)