UPDATED: Copy Tracks to Multiple Playlists v6.1
For macOS 11 and later only This script will copy the selected tracks to one or more chosen playlists--or move them, after which they will be removed from the source playlist (if possible; tracks cannot be removed from dynamically populated playlists).
Also see Remove From Other Playlists.
Latest version:
- Adds "Move Tracks"
- Minor UI and performance enhancements
More information for Copy Tracks to Multiple Playlists v6.1 and download link is here.