On the Amazon Firestick, this is super easy, you just enable the Developer Tools Menu and it shows you what the input bitrate is for both the video and audio, as well as what video and audio codecs are being used.
What is the easiest way to do this on Android TV? I'm using Android 9 Pie on a 2019 Sony 950G.
How do you enable that Developer Tools Menu? I just have Developers options where you can enable ADB and allow unknown sources apps installation
On my Hisense H8G it's under Menu > Help > Signal information, I'm not sure how you do it on Sony
Kodi has a shortcut to do so
Plex, Kodi, Emby all provide it. Android TV doesn't provide it system wide.
Look under developer settings. If you haven't enabled it already it's the same way you'd do it on android. Settings>about>then click on build number until it says it's enabled