Answers to Gospel Questions 1:171; “…Abraham, Joseph, and Moses married women of their own race, and we need have no worry over our lineage, because we are of that same race.”
Galatians 3:16; “Now to Abraham and his seed were the promises made. He saith not, And to seeds, as of many; but as of one, And to thy seed, which is Christ.”
Actually Joseph married Asenath, an Egyptian woman. She was given to Joseph as a gift from the pharaoh in appreciation for what Joseph had done for Egypt. (Gen. 41:45) Asenath and Joseph had two sons; Manasseh and Ephraim.
Secondly, the Mormons are not a race of people so how could they be Egyptian or Hebrew?