I want to configure a tool so that I can just call with a movie as an argument and automatically download the appropriate english subtitle by file hash or name. I recall I had something configured like that but now I don’t remember what was the tool I used.
There are scripts for MPV that do this
https://github.com/davidde/mpv-autosub
https://github.com/joaquintorres/autosubsync-mpv
You’d expect MPV was published by MIT or Bell Labs in late 1970’s because it is so good, can do literally anything while remaining lightweight. But no, it is released in August 2013.