Ahha! Yep, my bad, you can indeed use the poster.ext or fanart.ext. I missed that in the article regarding fanart but for poster only poster.ext seems to work…
So when adding a new movie and refreshing metadata, Plex pulls the movie info, certification, actors, etc, from the nfo and the fanart created by EMM however I always have to add the poster manually, which is frustrating.
Again, it seems odd that Plex allows 2 filenaming conventions for fanart but not poster. It would make sense to me to be consistent and either allow both naming conventions or only one…