Tone is a cross-platform metadata editor that allows you to modify metadata for various formats, including mp3, m4b, and flac. It has no dependencies and can be downloaded as a single binary for various platforms, written in pure C#. You can use it to dump metadata, modify tags, and tag audio files with different kinds of metadata. It supports an extensive list of default fields like album, artist, and custom fields, covers, chapters, etc. In addition to this, you can also write your own JavaScript taggers and call functions with parameters to modify metadata. Tone can be downloaded from the releases page and is also available on DockerHub.
https://github.com/sandreas/tone