fb2 to txtz conversion represents export of ebooks from FictionBook e-book format (.fb2) to simple text based (zipped) ebook file labeled as .txtz file. You can certainly do this either manually by copying out the content of the .fb2 file, making a text file, compressing to ZIP archive and renaming the suffix. Or you can automate this by using one of the ebook management tools.
Updated: August 15, 2023