YHWSO
Son of God, Messiah
Matthew 1:21 (TS2009)
And she shall give birth to a Son, and you shall call His Name YHWSO for He shall save His people from their sins.
The Son of God was born as a Jew to Jewish parents in Bethlehem. He lived in the area of Galilee most of His life. He spoke Aramaic which is closely related to Hebrew. He spoke Hebrew (Acts 26:14). In Nazareth where He grew up He read from the Scroll of Isaiah which is originally written in Hebrew (Luke 4:16-18). When He was impaled there was an inscription written above Him "THIS IS THE KING OF THE JEWS" in Greek, Roman and Hebrew (Luke 23:38). There can be no doubt that He had an Aramaic or Hebrew Name. The Scriptures teach that the Name of the Son of God stands for salvation.
Yehoshua
His Name is most likely similar to the Scriptural name Joshua which comes from Yehoshua (Numbers 13:16) which means "God is salvation". According to Strong's Concordance the name Yehoshua comes from God's Name Yah and the word "yasha" which means "to save" or "salvation". So most likely the Hebrew Name of the Son of God consists of the Hebrew letters Yod He Waw Shin Ayin. Transliterated from Hebrew to English it is YHWSO. See also Zechariah 6:11-13.
Immanuel
Isaiah 7:14 (TS2009)
Therefore YHWH Himself gives you a sign: Look, the 'almah' conceives and gives birth to a son, and shall call His Name Immanu'el.
Matthew 1:23 (ESV)
Behold, the virgin shall conceive and bear a son, and they shall call his name Immanuel (which means, God with us).
The name of the Old Testament prophet Isaiah, or Yeshayah in Hebrew, consists of the words yasha, which means 'to save' or 'salvation', and Yah, the short form of the Name of God. So his name means 'salvation of Yah' and he prophecied the coming of the Messiah whose Name means 'God with us'. The oldest Isaiah scroll dates to well before the coming of the Messiah.
Pronunciation?
I found no conclusive evidence for the correct pronunciation of the Name YHWSO. If the correct pronunciation were important God would have preserved it. More important than the pronunciation is to know that He represents God and brings salvation. The Greek texts of the New Testament have the hellenized name Jesus written. But it's practically certain that He had a Hebrew Name. Therefore I make use of the transliteration YHWSO on this website. In the end I believe it's not so much about how the Name is written or pronounced, but more about what the Name stands for. The message of the New Testament is of course not exclusively for the Hebrew speaking world, but for the entire world (Matthew 24:14, Mark 16:15).