butterchurn VS audacious

Yes, the visuals are from the same tradition as old winamp plugins: https://github.com/jberg/butterchurn

Butterchurn Visualizer

yes, it is possible. there’s instructions on their github.

You can run Milkdrop 2 in a browser via this website.

I use this: https://butterchurnviz.com/

The input video was screen recorded from https://butterchurnviz.com/, using preset "martin - witchcraft reloaded".

I usually just use mpv since it's the simplest and most flexible. You might be looking for something like Audacious though, which is great too

Audacious is a more popular media player app that supports Winamp skins and a media library.

This may interest you,and it is Qt,plus can be used with MPD. https://audacious-media-player.org/

the new version of audacious has a vu meter and its also available to windows https://audacious-media-player.org/

Audacious audio player.

Find a GUI player you like (see https://wiki.archlinux.org/title/List_of_applications#Graphical_13 for a non-exhaustive list; ISTR Audacious being mentioned as a Winamp clone) and add it to your autostart items (see https://wiki.archlinux.org/title/Autostarting#On_desktop_environment_startup).

Yes, Winamp works well on Linux through wine, I have been using it for a long time myself. Although recently I have also been using audacious, which runs more smoothly and is better integrated with Linux (as it is a native application) and it also has support for Winamp skins, so it's a fairly good drop-in replacement (as long as you're not relying on some esoteric plugins or file formats).

im not the parent commenter but i highly recommend audacious for linux and windows. plays every audio format you have, doesn’t enforce a specific music library folder structure, and supports winamp skins(!) https://audacious-media-player.org/

Effectively succeeded by Audacious:

https://audacious-media-player.org/

... which is under active development/maintenance.