Needs:

• collection.xml (exported from rekordbox)
• newrekordbox.xml (will get overwritten by the script)

How to run:

• export rekordbox collection and paste it here
• yarn
• Write cue metadata with Mixed in key
• change baseDir to the dir with the tracks
• node index.js
• copy new xml to rekordbox.xml and put it in Library/Pioneer/rekordbox.xml
• On rekordbox, move songs from rekordbox.xml/collection to the main window and their db will get updated

Enjoy!