Then why should we use a Hebrew name if the Gospels are written in koiné helleniké? It would be ιησους then. But that is not His purpose here, guys.
Why does God let him call His Son either Jesus or Jesús or Jesu or any other name? Well, Sue already mentioned what happened in Babel, but there is another reason, He wants people of all nations and tongues to worship Him! That is another way how He can show us all His Glory, His Might and His Wisdom!
Revelation 7:9-10
9 After this I beheld, and, lo, a great multitude, which no man could number, of all nations, and kindreds, and people, and tongues, stood before the throne, and before the Lamb, clothed with white robes, and palms in their hands;
10 And cried with a loud voice, saying, Salvation to our God which sitteth upon the throne, and unto the Lamb.
Matthew 28:19 "Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost:"
Matthew 24:14 "And this gospel of the kingdom shall be preached in all the world for a witness unto all nations; and then shall the end come."
Matthew 25:31-32
31 "When the Son of man shall come in his glory, and all the holy angels with him, then shall he sit upon the throne of his glory:"
32 "And before him shall be gathered all nations: and he shall separate them one from another, as a shepherd divideth his sheep from the goats:"
Mark 13:10 "And the gospel must first be published among all nations."
All languages are another sign themselves of the end of times!