As a quick Google search will reveal, Catalina has spoiled audiobook management in a big way. It is no longer possible to edit audiobook metadata, as it was possible using iTunes in earlier versions of macOS. However, what puzzles me is that I downloaded a third-party tag editor (kid3), successfully edited the audiobook metadata and, even so, when I import the audiobook into the Books application, the metadata is wrong. What could be happening? Could the Books application use cached metadata from a previous import? Is there any way to avoid this problem?