Board Thread:Questions and Answers/@comment-31522209-20170317011443/@comment-246292-20170317013638

Khalid Nassour and Kent Nelson are on Prime Earth (though Nassour hasn't appeared yet in a Rebirth-titled book, there's no reason to think he is somehow retconned out). They are the only ones currently in the main DC Universe.

Khalid Ben-Hassin is shown on Earth 2, Jared Stevens is shown on Earth 13, and a separate version of Kent Nelson is shown on Earth 20. These are all Multiverse versions though.