So I've rewatched the movie (if anyone wants to I can DM them the link on fanfiction.net, but not here. Antvasima says I'm not allowed to post streaming site links on this wiki)
First, Vision is stabbed. So we know they are 7-B with their weapons, just like Cap is 8-A with his shield. Then Scarlet Witch is knocked aside by some sort of blue blast, which is not a surprise, since Scarlet Witch has only human durability. Corvus steps on Vision and tries to remove the Mind Stone with his weapon (again his weapon is 7-B), but Scarlet Witch attacks and rekts the two. She levitates herself and Vision away. Scarlet Witch heals Vision. (what power is that?)
Then Corvus grabbed Vision by a sneak-attack and pins him against a wall. (maybe PIS, or maybe Corvus just caught him off-guard). Proxima Midnight attacks and Scarlet Witch holds back with her magic. Then Vision easily overpowers Corvus. Scarlet Witch fights defensively and blocks Proxima's attacks, only to be knocked away by that blue blast again. Scarlet Witch blocks Proxima's attack.
Vision pins Corvus to a wall and beat him up. Vision is far stronger and hurls him aside. Corvus blocks Vision's blast with his weapon (again a feat for his weapon, not him), then redirects it back to Vision, bringing him down. (Feat for Vision actully, Corvus just redirected his own energy) Scarlet Witch starts fighting seriously and rekts Proxima Midnight.
Corvus attempts to remove the Mind Stone and gets rekt by Scarlet Witch. Proxima Midnight blasts Scarlet Witch again with that blue blast. They fall into a room. Then Cap, Falcon and Black Widow arrive, and defeat the aliens.
Conclusion: Proxima and Corvus never physically overpowered Vision. In fact, it's the other way round. Proxima harming Wanda is not even a feat, Wanda is just human durability. When Wanda is anxious that Vision is attacked, she rekts Proxima. Vision overpowers Corvus, Corvus only harmed Vision with weapons.
Proxima and Corvus should scale to Cap. Cull scales to Hulkbuster, maybe Bleeding Edge, while Ebony scales to Thor via telekinesis, unknown physically.
I disagree Proxima and Corvus scaling to Vision, I think they scale to Cap, @Matthew Schroeder Do you want to reply? Or do you agree with me?