If you are collaborating with a film club or a group of editors, do not use "My Drive." Create a Shared Drive (formerly Team Drive). Shared Drives keep files owned by the group, not an individual. If you leave Google, the movies stay.
Google actively scans files uploaded to Drive. They use a technology called Content ID. google drive folder movies
For tech-savvy users, Rclone is a command-line tool that mounts your Google Drive as a local disk. You can then point Plex or Jellyfin to that mount point. This effectively gives you an unlimited media server using Google Drive as the hard drive. Note: This strictly violates Google's fair use policy for Workspace accounts. If you are collaborating with a film club
For movies in foreign languages, upload the subtitle file (.srt or .vtt) to the same Google Drive folder. Rename it exactly like the movie: When you play the movie, click the "CC" icon in the player
When you play the movie, click the "CC" icon in the player. The subtitle will automatically appear as an option.