I have translated the author pages and category pages in /en/ and /fr/ version. But in category sitemap some of the /en/ URLs are missing and in author sitemap none of the URL of translated version are showing niether /en/ nor /fr/.
Authors' page are *real* pages? Or they're just some kind of template? Did you translate the texts via String Translation? If that's the case, they can't appear in the sitemap.
Fields group are not pages, they're similar to strings. If you're using Fields group, it's expected you don't see the authors' "pages" in the sitemap as they are not really translated pages.
At the moment there's no way to add them to the sitemap.
If you tell me which categories have the issue I'll check them.
Calculator is also a custom post type (authors is not) so there are actual posts being translated. The fields you see there are fields related to that kind of post type, not the only content you translate.
A custom post type "author" would be in the sitemap, yes, but "authors" in WordPress are a bit different so I'm not sure you can achieve the same result.
hidden link is in the sitemap. hidden link is not in the sitemap because you don't have enabled the option for directory in the default language - if you see there are no categories with the /en/ in the URL.
hidden link is not in the sitemap because it's empty. If archives have no content inside, they do not appear in the sitemap.