Hallo Manuti, for change Desktop Language to Spanish you must install more/other language Packs.
apt-get install task-spanish-desktop <- Spanish Desktop
apt-get install iceweasel-l10n-es-es <- For Spanish or iceweasel-l10n-all for All language packages for Iceweasel - Transitional package
after new installation Armbian, i installing additional packages:
apt-get install exfat-fuse exfat-utils <- For exFAT formatted drive
apt-get install synaptic policykit-1-gnome <- Graphical package management / GNOME authentication agent for PolicyKit-1
apt-get install gvfs gvfs-bin gvfs-backends <- Mount/Umount Network Drive User Space
apt-get install gnome-system-tools <- Cross-platform configuration utilities
apt-get install task-german-desktop <- German Desktop for German user
Now, after Reboot my Desktop Language is change.
before that is changed , only the following must be done:
I hope it helps you, jti