@Jordan1 You can use one controller to swap between Chromecasts but you'll need to follow these steps each time:
There has to be a better solution? Stadias's whole thing is move from one screen to another with ease, this is far from that. I'm going to buy another chromecast ultra for the same purpose. Currently if i hit the stadia button on my controller it wakes up the chromecast ultra, so now both TV's will turn on or just the last one i played from? They need to figure this out asap.