Launchpad currently recommends translating gnome-desktop3 in Ubuntu Cosmic.

Template "gnome-desktop-3.0" in Ubuntu Cosmic package "gnome-desktop3"

Language Status Untranslated Need review Changed Last Edited By
Cherokee 100.00  100.0% untranslated 27 27 0 0
Dakota 100.00  100.0% untranslated 27 27 0 0
Hawaiian 100.00  100.0% untranslated 27 27 0 0
Inuktitut 100.00  100.0% untranslated 27 27 0 0
Lakota 100.00  100.0% untranslated 27 27 0 0
Ojibwe 100.00  100.0% untranslated 27 27 0 0
Spanish 000.00  100.0% translated 0 0 2 2 2018-10-01 12:08:22 UTC 2018-10-01 Daniel Mustieles
Tlingit 100.00  100.0% untranslated 27 27 0 0
Yiddish 100.00  100.0% untranslated 27 27 0 0 2018-10-01 12:11:39 UTC 2018-10-01 Raphael Finkel
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Key to this table: “Unchanged” means Translated
and “untranslated” means just that, Untranslated

Other versions of gnome-desktop3 in Ubuntu