I don't think there is any self-hosted server that has a good playlist generation and is fully local, because it would need someone to classify the music in order to work. You can try to connect it to last.fm. I think Jellyfin has the addon for it.

Don't know about the playlist generation, but I like FunkWhale and it's federated too!

(And yess, I own the domain funkwhale.world... )

Someone did an ml project, pulled data tags from Spotify. It's very much a development project, and he only did it for one artist. He gave quite a bit of detail on how to to it and how to improve it. https://dev.to/mage_ai/using-machine-learning-ml-to-generate-the-ultimate-taylor-swift-playlist-50e8

Plex has sonic analysis and that is great for music recommendations. Are you looking to discover new music? That is difficult to achieve when you are just using music you downloaded.

I use Plex/PlexAmp for music in my library, and I scrobble to Last.fm from my plex server and visit their site from time to time to discover new music.

There's this one called lightweight music server. It's basically just a glorified in-browser vlc. It has playlists and remembers what you were doing if you close the browser but it's not possible to move songs up or down in the playlist. You can add songs to the front or back of the playlist as well as remove songs from the playlist but there's no dragging up or down. For me it's still the more desirable choice vs using Spotify and either paying a monthly fee or listening to ads. I know there are anti ad hacks but they always break after every update and are hard to install.

I have been planning on giving this a try but havent had a chance yet: https://github.com/koel/koel

It looks pretty neat, hopefully it can do what you mentioned as well.

It looks like plexamp can do this. It’s self-hosted, so you can add your own music files. It’s paid and I haven’t used it, so I can’t give any more info.

Plexamp has completely replaced streaming services for me. Plex will now sonically scan any music you add and is able to give recommendations through Plexamp for sonically similar tracks, and also use that data to build mixes based on mood and style.

There are all sorts of auto generated mixes that Plexamp will make on it's own based on the music you have. You can also make a playlist of say, your top 20 tracks and when the playlist ends Plexamp will just start playing songs that match the sonic theme of what you've been playing so far. Note that I say sonically similar rather than of a similar genre. I love this because genres are often very subjective, and while Plex does take into account the tags you've given things, it also will group songs based on how they actually sound. You can control how many degrees of separation too if you want to keep the theme close to your playlist or just let it wander through your collection.

For me at least, Plexamp is every bit as good as Spotify. My music collection has grown to around 20,000 tracks over the years and it's pretty easy to get stuck on the same handful of artists. Mixes and auto playlist generation in Plexamp has helped me rediscover music I forgot I even have.