You're absolutely right that calibre has
"Swap title and author", both in the single-book editor and in bulk edit. But
that feature does something quite different from what this plugin is for, and it wouldn't solve the problem it targets:
- Calibre's swap is blind and manual. It just exchanges the Title and Author of whatever books you select — it doesn't tell you which books are actually wrong. In the real case this addresses, you have a library with thousands of books where only some are swapped, mixed in with correctly-cataloged ones. If you select a group and tick "Swap title and author", you'd corrupt all the correct ones too. The hard part is identifying the affected books — and that's exactly what the plugin does automatically.
- It reads the .epub's internal metadata, not just the record. The plugin opens each book's OPF (dc:title/dc:creator) and compares it against the calibre record to detect the genuinely-swapped ones. Calibre's swap only looks at the record.
- It recovers accents where the file preserves them. In these imports the swap usually also comes de-accented. The correct author (with accents) is normally kept in the OPF file-as/sort fields, and the accented title in the calibre:title_sort or NCX metadata, so the plugin restores those; a blind field swap would just keep the accent-less text. Where the file doesn't carry the accented form, that field is left as-is for you to touch up.
- It can fix the .epub interior too, not only the record — and it has a third mode that detects record/epub mismatches.
Calibre's swap never touches the file.
- Everything is reviewable per book before applying: you see the proposed title/author, can edit it, pick only the title or only the author, and apply only the ones you tick — so correct books are never touched.
So it's not a replacement for the manual swap; it's an automated
detect-and-fix tool for a specific kind of corruption (swapped + de-accented metadata baked into the files) that the built-in swap can't identify on its own. Thanks for raising it — it's a fair point worth clarifying in the thread.