I have already said that. Are you willing to argue that those in the Old Testament actually knew that the Messiah was going to be Jesus of Nazareth?
Of course those in the Old Testament times knew of many prophecies which were in regard to the promised Messiah, such as Isaiah 53, but they didn't know that the Messiah would be Jesus of Nazareth.
They knew Messiah would be God's Salvation to His People regardless of how He looked like. Simeon said Lk 2:26-32
26 And it was revealed unto him by the Holy Ghost, that he should not see death, before he had seen the Lord's Christ.
27 And he came by the Spirit into the temple: and when the parents brought in the child Jesus, to do for him after the custom of the law,
28 Then took he him up in his arms, and blessed God, and said,
29 Lord, now lettest thou thy servant depart in peace, according to thy word:
30 For mine eyes have seen thy salvation,
31 Which thou hast prepared before the face of all people;
32 A light to lighten the Gentiles, and the glory of thy people Israel.
Simeon had Faith in Christ before Christ was born, even though he had opportunity to see Him physically and the physical circumstances He was born. Those things only validated his faith in Christ.
Believers for the most part have Faith in Christ without actually seeing Him 1 Pet 1:7-8
7 That the trial of your faith, being much more precious than of gold that perisheth, though it be tried with fire, might be found unto praise and honour and glory at the appearing of Jesus Christ:
8 Whom having not seen, ye love; in whom, though
now ye see him not, yet believing, ye rejoice with joy unspeakable and full of glory: