I liked the search query in opensubtitels.org esp. the way to ask for subtitles using imdb, although it may be useful to even include tmdb.org as well.
I don't see a way in the current way to search for movies using the imdb.com or tmdb.org unique IDs
For instance 8267604 in imdb and 517814 at tmdb https://www.themoviedb.org/movie/517814 ... uage=en-US
Would be nice to have such a way.
Update 11/03/19 - On the response I tried the solution and it doesn't work :(