The word "User Functions" when changed to something else eg "User Zone" or "User Vault" etc in the block editor in admin panel
does get changed for the loggeg in user, however it still shows "User Functions" for non logged in user above the name and password boxes ..... Can there be any hard coded change to affect it as wished ??

When you're not logged in, the text is pulled from the language file, see Where can I change the text ...?

bye, Dirk