MusicBrainz Picard is described as 'Picard is the next generation MusicBrainz tagging application. This new tagging concept is album oriented, as opposed to track/file oriented like the ClassicTagger was. Picard is written in Python, which is a cross-platform language, and makes use of cross-platform libraries -' and is a very popular Mp3 Tag Editor in the audio & music category. There are more than 50 alternatives to MusicBrainz Picard for a variety of platforms, including Windows, Mac, Linux, Android and Web-based apps. The best MusicBrainz Picard alternative is Mp3tag, which is free. Other great apps like MusicBrainz Picard are Kid3, TagScanner, beets and Puddletag.
Metadatics is excellent and clearly overlooked ID3 tag editor for Mac. It's thorough and well-designed with all that you need and nothing more. Users of Mp3tag on Windows should feel right at home after just a bit of getting used to it.