Sometimes I think people's patent ability to misunderstand each other is a left-over from the Tower of Babel
I view God as Omnisciencent, and that is how He chose us from before the beginning. I do not view humans as pre-existant. That said, the Ephesians verse alone could be used to support a pre-existant humanity...
Now back to topic:
Jesus according to John while speaking to Jews in the first century AD also was existing before Abraham was.