I don't think many people are getting what he's asking. Here's the poster he's talking about:
Kingdom Hearts Ultimania - Image Viewer
The question was who's the guy who "looks like Roxas" on the 358/2 Days segment (the right). That's just Roxas. They just drew him a little different, but it's Roxas.
Just in case you didn't know, there are three new KH games coming out (which all connect to KH3):
Birth by Sleep - Takes place 10 years before KH1. Stars Terra, Aqua, and Ven.
358/2 Days - Takes place in between CoM and KH2. Stars Roxas and Organization XIII.
Coded - Takes place after KH2. Stars Mickey, Jiminy, and a virtual Sora.
In Birth by Sleep, one of the three main characters looks
exactly like Roxas, as you can see on the Birth by Sleep segment on the poster (the left). But he's not since Roxas wasn't even born at that time. His name's Ven, and he's a totally different person. Ven's identity is the main theme of the game. The other game, 358/2 Days, stars the actual Roxas.