The method I posted is for attaching the camera to one specific character. Since you mentioned Marvel Vs Capcom 2, I thought I should add that it will take a bit more than this, as the camera in that game is more of a separate entity that moves based on the two fighters positions. on screen.
This would require a bit more logic than what I have presented. For that purpose, it would require a blueprint graph that updates the camera position on tick.
Youd have to have references to your 2 characters in the camera blueprint, and have the cameras location change based on the location of those characters. How the camera moves etc would be up to you.