@simonferndriger said:
Best way to select arthouse movies
What is the best way to get all arthouse movies?
Using the genres this does not seem possible at the moment unfortunately...
could this genre perhaps be added?

I don't think so.
Anyway, if you want to propose a new genre, I suggest posting your request in the conversation below.

Genre

There is a topic specifically for Genre .
https://www.themoviedb.org/talk/51b5fe1a760ee359996a0e62
And we have one for translating the Genres.
https://www.themoviedb.org/talk/508aa4f619c2951bd00002a8

This implementation work has been stalled for some time.
But I believe that when work is resumed, this will be the basic topic for implementation.
So I suggest you post your request there.