After some troubleshooting with Aman to determine that directory structures with symbolic links are not supported, I was able to successfully import my local movie library, which has the following structure (guided by other community posts, and Plex naming convention):
/Movies
/Movie Name (year)
Movie Name (year).mpg
DVR server version is: 2021.01.15.1649, running on a QNAP NAS.
There are only a handful of movies that did not import with proper metadata. I did verify the naming on both IMDB and TMDB to be correct. I also tried appending to the directory name and filename additional metadata in the form {[source]-[id]}. I tried first TMDB, and then performed a [Prune Deleted] followed by [Scan Sources] maintenance actions in Channels Settings, then tried IMDB and followed the same maintenance procedure. None dereference metadata. I can see a SCN log event showing the updated name of the directory/file being imported.
Also, from what I can tell, no local poster art will be imported. I have tried Folder.jpg and Poster.jpg in the same directory as each movie. Please advise if there is a means to leverage local poster art or even a JSON or XML file with metadata. I don't see this documented anywhere, but may have missed it.
These specific movies in my library are not showing any metadata being pulled when I name directory/file as outlined above without imdb or tmdb hint, or even if I do specify the specific ID for imdb or tmdb. All other movies with no imdb or tmdb hints are pulled correctly into the library. Note that when I search either IMDB or TMDB with the exact string, the correct movie is found.
/Movies
/8 Mile (2002)
8 Mile (2002) {tmdb-65}.mpg
8 Mile (2002) {imdb-tt0298203}
For each of the movies, I tried 3 names, and none work.
17 Again (2009)
17 Again (2009) {tmdb-16996}
17 Again (2009) {imdb-tt0974661}
Best of the Chris Rock Show - Volume 1 (1999)
Best of the Chris Rock Show - Volume 1 (1999) {tmdb-711927}
Best of the Chris Rock Show - Volume 1 (1999) {imdb-tt0500094}
I, Robot (2004)
I, Robot (2004) {tmdb-2048}
I, Robot (2004) (imdb-tt0298203}
X-Men (2000)
X-Men (2000) {tmdb-36657}
X-Men (2000) {imdb-tt0120903}
Die Hard - Live Free or Die Hard (2007)
Die Hard - Live Free or Die Hard (2007) {tmdb-1571}
Die Hard - Live Free or Die Hard (2007) (imdb-tt0337978}
This Die Hard one actually matches/pulls wrong movie metadata for "Live Free or Die (2006)"