I'm currently using Yattee, but it relies on Invidious to access YouTube, so I always have to switch instances around to get videos to load. It's also pretty unstable.
I use an app called yattee, but it won't be set up out of the box. It allows you to use invidious and piped instances to play YouTube videos. Yattee is just an app that can play remote files. There is a github json file with all the public invidious and piped instances which can be added in the yattee app and it works pretty good most of the time. It also allows you to easily switch between servers if one isn't working. Here is the guide I used to get it set up
I use this myself for when I want to be signed-in. However, it's not a very private alternative, since YouTube will still track you on the app even when signed out and with history disabled