When you highlight the portrait of the following characters and hold START, you'll see their other portrait in the bottom left or right corner change. Press X, Y, A, or B (while holding start) to select a different version of that character.

The following are available:

Kyo, Terry, Andy, Joe, Ryo, Robert, Yuri, Mai, Yashiro, Shermie, Chris, Billy, & Rugal.