I’ve asked about FTP access, not Cpanel.
You can translate untranslated strings now – http://prntscr.com/otx67u , but I would recommend you to rename fr_FR.po, fr_FR.mo files to xstore-fr_FR.po, xstore-fr_FR.po and move them from /wp-content/themes/xstore folder to /wp-content/languages/themes/ folder.
