OET interlinear 2 KI 19:30

uW Translation Notes:

Note 1 topic: figures-of-speech / metaphor

וְ⁠יָ֨סְפָ֜ה פְּלֵיטַ֧ת בֵּית־יְהוּדָ֛ה הַ⁠נִּשְׁאָרָ֖ה שֹׁ֣רֶשׁ לְ⁠מָ֑טָּה וְ⁠עָשָׂ֥ה פְרִ֖י לְ⁠מָֽעְלָ⁠ה

and,it_will_add (Some words not found in UHB: and,it_will_add remnant_of house_of Yehuda [which],remains root (to),downwards and,it_will_produce fruit (to),upwards, )

Isaiah is speaking as if the Judeans were actually a plant that would take root and make fruit. If it would be helpful in your language, you could state the meaning plainly. Alternate translation: [And the Judeans who have survived and remain will establish themselves in their land again and have many children]

Note 2 topic: figures-of-speech / abstractnouns

וְ⁠יָ֨סְפָ֜ה פְּלֵיטַ֧ת בֵּית־יְהוּדָ֛ה הַ⁠נִּשְׁאָרָ֖ה

and,it_will_add (Some words not found in UHB: and,it_will_add remnant_of house_of Yehuda [which],remains root (to),downwards and,it_will_produce fruit (to),upwards, )

If your language does not use an abstract noun for the idea of survival, you could express the same idea in another way, here and in the next verse. Alternate translation: [And the remaining survivors of the house of Judah]

Note 3 topic: figures-of-speech / metaphor

בֵּית־יְהוּדָ֛ה

(Some words not found in UHB: and,it_will_add remnant_of house_of Yehuda [which],remains root (to),downwards and,it_will_produce fruit (to),upwards, )

See how you translated the similar expression in 8:12. Alternate translation: [the descendants of Judah]