Fight as Chun Li in Street Fighter 2 costume
Enter the character selection screen. Highlight Chun Li. Hold Start for five seconds and press any button. Alternatively, highlight Chun-Li on the character selection screen, hold Start, and press A + B + X.
Fight as Evil Ryu
Enter the character selection screen. Highlight Ryu. Press Start, then press Right to Adon, Up to Akuma, Down to Adon, and Left to Ryu. Then hold Start and press all three punch or kick buttons.