Sounds like deadbeef
I remember using foobar2000 on windows and then trying out deadbeef on linux. The problem is it falls into a demand gap on linux. People drawn to foobar2000 tend to be power users but on linux there is way more options available for power users.
Like how the author enjoys the directory based music browser for the exact same reasons I did. My music wasnt tagged correctly but it was manually sorted correctly by me. On linux the solution is to use beets to automatically sort and correctly tag all of your music.
Then there's the issue of the player. On linux the titan is MPD, a music player server. MPD has no UI but and client can have any UI it wants. Then you get stuff like, mpc, ncmpc, ncmpcpp, cantata, etc. Once you learn about all the possibilities of MPD, you dont want to use a foobar2000 clone unless its a MPD client.
Also writing plugins in a custom language (fooscript) is usually a bad idea. Just use Lua. Its literally what lua is built to do.