There aren’t really “advanced” tutorials similar to what you’ve described. When making plugins the only Capacitor-specific step you need is to use the plugin API to send data back and forth from web <–> native. Making a native video player using Exoplayer or AVKit is doable, but does require a lot of knowledge of native APIs for programmatically displaying the video containers. Your best bet right now is to look at how existing Capacitor plugins work and read the docs for both AVKit and Exoplayer.
That being said, the team is planning on making more docs and tutorials on how to make plugins; but a lot of what you’re describing is more knowledge of Android/iOS APIs and not really related to Capacitor APIs.