Launchpad currently recommends translating grub2 in Ubuntu Zesty.

Template "grub" in Ubuntu Zesty package "grub2"

Language Status Untranslated Need review Changed Last Edited By
Cherokee 100.00  100.0% untranslated 1370 1370 0 0
Dakota 100.00  100.0% untranslated 1370 1370 0 0
Hawaiian 100.00  100.0% untranslated 1370 1370 0 0
Inuktitut 100.00  100.0% untranslated 1370 1370 0 0
Lakota 100.00  100.0% untranslated 1370 1370 0 0
Ojibwe 100.00  100.0% untranslated 1370 1370 0 0
Spanish 002.19  97.8102189781% translated  2.1897810219% untranslated 30 30 0 3 3 2017-06-22 01:40:23 UTC 2017-06-22 Miguel Ángel Arruga Vivas
Tlingit 100.00  100.0% untranslated 1370 1370 0 0
Yiddish 100.00  100.0% untranslated 1370 1370 0 0
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Key to this table: “Unchanged” means Translated
and “untranslated” means just that, Untranslated

Other versions of grub2 in Ubuntu