I haven't used LIbreOffice in awhile.  The documentation indicates that you press control+page down to move to the footer - is that correct?  I got it from: https://help.libreoffice.org/Writer/Shortcut_Keys_for_Writer

I'll have to try it - I've been mostly concentrating on Microsoft Office lately as I've been writing the training material for that office suite, but I would like to get to LIbreOffice or Open Office.

In any case, if footnotes aren't reading, it would be worth filing an issue on our GitHub page: https://github.com/nvaccess/nvda/issues  Having a quick look, I can't see one already for this issue.  There is one for an error being generated in NVDA's log when you add footer text then switch to another program and back.  I wonder does it read the footer if you try immediately after creating it, and then not if you switch programs and bacK?

Regards

Quentin.