S.R.L/ I would answer yes, but in different ways because of God’s foreknowledge or mind and the Scriptures (Rev 13:8), (I Peter 1: 18-20), (Gal 4:4), (Heb 2:9). Therefore, he had existence in God’s foreknowledge.
Another way that the Son of God could pre-exist was as the Word of God( Logos). In other words, the Son of God did Pre-exist , but not as the Son of God: As the Word of God instead.
He who was the Word of God in the Old Testament became the Son of God in the New Testament. The male person born of Mary did not Pre-exist as a Son for the results of this would mean a Pre-existent human being. However, this does not change the fact that He who was the Son of God in the New Testament, had existed before in a different form. God in Christ in both testaments. Christ has always been the visible temple of the invisible God.

(“If ye knew these things” by Ross Drysdale chpt.15 pgs.1-3)

I can relate to this God in Christ author better than others. I have never seen or heard the God in Christ message taught this way.