Board Thread:Questions and Answers/@comment-98.35.170.200-20200922232337/@comment-35248429-20200923191609

There is no version of Kirito in the Underworld.

1. Kirito and Asuna are removed from Underworld.

2. Kirito and Asuna request their memories of the 200 years be deleted.

3. Higa copies Kirito's fluctlight while Rinko and Kikouka aren't looking.

4. Higa deletes Kirito and Asuna's memories of the 200 years.

I though this was pretty clearly explained in the anime. The copy is the one with 200 years of memories in a light cube on Higa's desk.