Here my own idea of mortal kombat vs street fighter rivals list.

Liu kang vs Ryu both are world heroes champions.

Kung lao vs Ken master both friendly rival of Ryu and Liu kang.

Raiden vs Gouken both mentor to Liu kang and Kung lao and Ryu and Ken .

Akuma vs Shinnok both are Rivals of Gouken and Raiden .

Kitana vs Chun li both blue female and lost there father from Shao Kahn and M bison .

Jax vs Guile .

Sonya blade vs Cammy white both blonde hair military.

Kano vs Balrog both are criminals.

Johnny cage vs Fei long both are movie martial arts Stars .

Baraka vs Vega both have blade .

Shao Kahn vs M bison both are main villians boss both killed kitana and chun li father.

Let me know if any you people got idea of rest Mortal kombat and Street fighter rivals characters.