A quite extraordinary Ryu, Ken and Mobi-Chan Easter-egg exists in the Japanese version of the 1992 coin-op Warriors of Fate, sequel to Dynasty Wars (based on the Tenchi wo Kurau manga). If the game is completed on one credit the player is treated to a special sequence after inputting their initials. In the normal endings (of which there are two, depending on whether or not you kill Akkila-Orkhan [aka Cao-Cao or Sou-Sou]) the credits roll immediately after the portrait picture of your character is displayed, but on a one credit run an additional scene is inserted containing dialogue from three bachelorettes and, astonishingly, a fight between two Mobi-Chan wearing Ryu and Ken costumes!
Corrupt cop Edi. E from Final Fight has a cameo in Street Fighter Alpha 3 whereby he can sometimes be seen chasing Cody off the screen after Cody wins a round. There are two versions of this cameo, in the first Edi. E simply chases Cody off the screen in comedic fashion. In the second (rarer) instance, Cody holds his ground and strikes Edi. E with a swift kick that sends the cop flying backwards and out of the scene. Cody's ability to pick up the knife (by crouching and pressing two punch buttons, repeated in Super IV) is a further homage to Final Fight as are a number of his win quotes, especially:
After waiting so long, it feels good to do more than two moves!
Cody's alternate costume in Street Fighter × Tekken, a policeman's uniform, is likely a tip of the hat to Edi. E as well. (See Volume III page three for that fact about Edi's bubble-gum!)
Karin's surname is Kanzuki and she is heiress to the Kanzuki Zaibatsu (an unimaginably wealthy financial conglomerate). The World Warrior Encyclopedia elaborates on her fortune and explains that the Kanzuki family are even wealthier than the Masters', even owning their own satellite, named 'Red Spider Lily' (or 'Manjushage'). Karen's entourage consists of Ishizaki (the pudgy servant who wears an apron and has humorous cameos at the beginning and end of some of Karin's fights in Alpha 3. Supposedly he's a former judo practioner) and Shibazaki (slicked-back hair, spectacles, visible in Karin's Alpha 3 ending and allegedly trained by Azam, Rashid's personal assistant, via online leaning sessions!) Karin is also notable for having been created by artist and author Masahiko Nakahira for the Sakura Ganbaru! manga, rather than in-house.
When ported to the TurboGrafx-16 console as Fighting Street, the original Street Fighter gained an additional part to its ending sequence. A segment showing Ryu climbing the steps of a jumbo jet, stopping to wave at the top as he returns 'home' from the Street Fighter tournament is entirely missing from the arcade original. Whilst on the subject of aeroplanes, the flights from location to location on the map throughout Street Fighter II actually originated in Street Fighter and the same can be said for the diverting bonus rounds and win quote splash screens, both staples of the Street Fighter series that break up the games' arcade modes (ironic then that bonus rounds were removed from the notioriously brutal Super Turbo!)
The Chinese tennis player named Li-Li in Capcom Sports Club: Starring Basketball Tennis & Soccer (1997) is a doppelganger of Chun-Li. The resemblance is too close to be mere coincidence and, combined with the name and nationality, this seems certain to be a deliberate reference. Considering that she is famous for her kicks and not for her backhand (!) 'Li-Li' might have been better suited to the football portion of Capcom Sports Club....
Akuma's ending in Super Street Fighter II Turbo was heavily cut for international releases. In the Japanese original, there are two extra portions of text depending on the ultimate character fought. If the last fight is against M. Bison the following is shown:
Akuma: Evil Emperor, you say... nothing more than words. Real victory can only come from a fist. That is all.
There was no one to stop Akuma from that moment onwards.
If the last fight is against Akuma (i.e. the conditions required for facing Akuma are met whilst playing as Akuma:
Akuma: Something within... what's this?
???: I am the shadow of the condemned. You have killed the demon of this curse, and so you shall be condemned no more!
Akuma: I now reside in darkness. Even death is beneath me... excellent!
...That man returned to the darkness and disappeared.
Cody's taunt in Alpha 3 makes it perfectly clear that his incarceration is completely under his own control as he can be seen undoing his handcuffs at will to shake out his sore wrists. Superficialy, it might be said that this puts him in the same company as Oro who deliberately handicaps himself in battle also. As depicted in his Alpha 3 background he is also able to punch through the walls of his cell should he feel like going out. On the details of Alpha Cody's appearance, it has been observed that the shoes he wears closely resemble Adidas Superstars whereas the shoes that Alpha Guy wears resemble Nike Dunks (but see Vol. II, page ten for what they used to wear in the Final Fight era!) One final tidbit, the kanji on Guy's top translates as 'God of War' or 'Warrior Spirit'.