Django Music Publisher (DMP) is open-source software for managing music metadata,
batch registration of musical works (using CWR) and royalty processing.
It was initially released in July 2018 and has been regularly upgraded ever since.
The current version 21.5 Mayday was released in May 2021.
Documentation: Release History
It comes with a great user manual and many video tutorials.
Django Music Publisher is free. MIT License
No registration, no payment data, no BS.