I can’t recommend Musicbee enough: https://www.getmusicbee.com/. It’s completely free, extremely customizable, updated consistently, has healthy ecosystem of plugins, and has a helpful community if you have questions about using any of its features.

Mediamonkey is also a good choice, but once I found Musicbee I transitioned and never looked back: https://www.mediamonkey.com/.

Edit: I forgot to add that both options support playlist and visualizers. Musicbee even has smart playlists that can update automatically based on custom rules you set up. (If you want that feature in Mediamonkey, then you have to pay for a license.)

Foobar2000 has become the new winamp for me, been using it for a decade now

for audio: foobar2000

for video: MPC-HC, MVP, VLC

I wouldn't recommend Clementine since it's unmaintained. You might want to consider Strawberry instead, which is an updated fork of Clementine.

That having been said, I actually use Audacious because I like using old WinAmp skins.

Fooyin, VLC, and Kodi.

I recently found this on github : Muzik-offline

I'm also keepin an eye on this as it has flac support : Wora

There are more on this list : Alternativeto

foobar and musicbee are not open source afaik

I recommend Tauon since it also has a Windows build.

i like cmus, but it is commandline-only.