If you use the older Chromecast dongle that doesn’t have android TV and no remote (the circular ones) you should be able to use castblock to auto mute ads and automatically press the skip button as soon as it shows up. It also has sponsorblock support so it will auto skip sponsor segments too. You just have to run the program on the same network with flags specifying you want it to mute ads, skip ads, and give it the list of sponsorblock segment types to skip and it’ll auto detect any Chromecasts and do it’s auto skipping and muting magic