M.Bison can be an extremely difficult opponent for Vega. Bison can oppress with tricky frame traps and he’s also quick and difficult to lock down.

Bison has good options against Vega at all distances:

At close range, he has nasty S.LK traps that are positive on block, meaning he can stay in your face while chaining them or look for a combo or tick throw. Reversing with a Scarlett Terror is a gamble with bad odds since he can usually recover fast enough to block and punish big. Instead, push him away with a quick S.LK and use the block stun to gain a little distance. Long blockstrings are not recommended, he can easily interrupt them with scissors kick. Instead, hit and run. Occasionally throw out a late C.HP which is a good move for trying to beat a scissor or standing kick.

From medium range, his normals tend to overpower your pokes and his Psycho Crusher / scissor kick are a little too fast to react to. C.HK Slide is risky but important to gain control. If Bison jumps at you full screen, you can sweep early, going under his hitbox as he’s landing. He can block this, but you’ll get big frame advantage at a great range and can jump on him, crossup or poke after. Once again, C.HP is the neutral button of choice as it stays out a long time and beats a lot of his offence.

At long range, it’s 50-50. Both characters can counter everything the other does, but your reactions have to be on point. Bison can headstomp or psycho crusher. Vega’s NJ.MK and J.MP counter headstomps. Vega’s J.HP cleanly hits Psycho Crusher. You often want to be jumping back and forth at full screen neutral so you can press a button on reaction to these moves. Vega can abuse wall dive on wakeup, Bison’s super is the only thing he has to reverse it. But other than that, Bison has a very fast high jump and his J.MP is especially good at hitting you out of all wall dive situations. Rely more on baits, steering very far away and putting the claw out early – this will hit him if he jumps forward for an anti-air J.MP.

Play Paper-Rock-Scissors in this match. If Bison wants to get in and oppress, stay long range, make him impatient, and calmly counter whatever he uses to get close. If he spams special moves, spam C.HP and J.HP back at him. When you knock him down, stay on him with HP Roll, then throw when you think you can get away it. Keep your pokes seldom and safe, only when you know a scissor kick isn’t going to beat you out.