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 23 23 0 0
Dakota 100.00  100.0% untranslated 23 23 0 0
Hawaiian 100.00  100.0% untranslated 23 23 0 0
Inuktitut 100.00  100.0% untranslated 23 23 0 0
Lakota 100.00  100.0% untranslated 23 23 0 0
Ojibwe 100.00  100.0% untranslated 23 23 0 0
Spanish 000.00  100.0% translated 0 0 2 2 2018-08-13 04:58:56 UTC 2018-08-13 Daniel Mustieles
Tlingit 100.00  100.0% untranslated 23 23 0 0
Yiddish 100.00  100.0% untranslated 23 23 0 0 2018-08-13 04:57:21 UTC 2018-08-13 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