Following are a number of back-translations as well as a sample translation for translators of Isaiah 6:13:

• Kupsabiny: “Even if a few people may remain in the land,
  their land will again be destroyed.
  Israel will become like an oak that has been felled
  to become a stump.
  A holy branch shall sprout from that stump.” (Source: Kupsabiny Back Translation)
• Newari: “Even if only one tenth of the people remain in that land,
  I will destroy them all. But having been cut [down] they have been made like a oak tree stump.
  For this reason, however, the holy seed in that land will be like a stump,
  it will grow again."” (Source: Newari Back Translation)
• Hiligaynon: “Even-if the tenth portion of the Israelinhon remain in the land of Israel, they will-be-destroyed too. But I have-chosen some/[existential marker] from them to-be-left-behind. They are like a stump of an oak/[terebinto] tree that was-cut-down.” (Source: Hiligaynon Back Translation)
• English: “If even one tenth of the people survive and stay there,
  their enemies will invade the land again and burn everything.
  But, just like when an oak tree is cut down, a stump is left from which new shoots will grow,
  the people who remain in this land will be a group that will become large again and be set apart for/dedicated to me.’” (Source: Translation for Translators)