The translations come as zips, and when you unzip them, you will get a (fairly complicated) directory tree with files in two places. The first will be a .conf file that will be in ~/mods.d/, and the actual text files will be in ~/modules/texts/[raw|z]texts/[translation name]/. My translations are in /mnt/card/usr/share/sword/... I would guess that /mnt/cf/usr/share/sword/ would work as well.