Following are a number of back-translations as well as a sample translation for translators of Isaiah 19:11:

• Kupsabiny: “The leaders of the city of Zoan know/understand nothing,
  they give foolish advice to the king of Egypt.
  The words of those people who take themselves to be wise are useless
  even if they descend from kings of old.” (Source: Kupsabiny Back Translation)
• Newari: “The Zoan city officials are really fools [lit.: very much fools],
  The wisest [men] of Egypt [lit.: In Egypt the ones who have the most wisdom of all] give evil advice.
  How can you say to Pharaoh,
  "I am one of the people who has wisdom,
  [I am] a follower of ancient kings."?” (Source: Newari Back Translation)
• Hiligaynon: “The officials of Zoan are fools/crazy! They are-recognized as the most-brilliant counselors of the king of Egipto, but what they counsel are of no value. How can- they -say to the king of Egipto, ‘We (incl.) are descendants of the wise people and of the kings long-time-ago.’” (Source: Hiligaynon Back Translation)
• English: “The officials in Zoan city in northern Egypt are foolish.
  The advice that they gave to the king was worthless.
  Why do they continue to tell the king that they are wise,
  that they are descendants of wise kings who lived long ago ?” (Source: Translation for Translators)