Isaiah 9: should read
For a child has been born to us, a son given to us, and the authority is upon his shoulder, and the wondrous adviser, the mighty God, the everlasting Father, called his name, "the prince of peace."
This is G-d talking about King Hezekiah.
The other two are too week to even derive meaningful theology from in my opinion. One of the rules for proper exegesis being that week and obscure passages dont dominate the strong and clear. Sorry, when you correctly translate the Hebrew, Jesus is not there in the Tanach. Only by forcing him there by isogesis.
If many witnesses testify that events have occurred and one version of understanding the OT contradicts the witnesses and another understanding conforms to the witnesses, which version is true?