“You might want to re-think that claim in light of Ephesians 1:4 ...?”
Your confusing the knowledge of something with the existence of that something.
I can have ‘some’ knowledge (like their names and such) of my future son or daughter long before I get married and have children (added that last part for clarification in these times). That doesn’t mean they exist.
By the way, I’m a grandpa so the preceding was only an example.
And then you have the question of whether we existing and God chose us, or whether God had a catalog of potential people on a shelf, and went, "Hmm, I think I'll make one John, a Mary, and two Marshas...no, not *that* Billy, I think I'll make the other one."
I don't think eternity maps very well to our present time-space continuum; the focus is blurred further by the Incarnation; and the question of whether, even in Heaven, we will have the same perceptions, the just knowing, that God has, or merely a version with training wheels (we are still only limited creatures), I don't know...
Any Hebraic / Aramaic / ancient Greek scholars available for help on the text?
Cheers!