The cannons most used by the Hs-129 were the MK101 and MK103. They shot the same carbide core round at high velocity, which at sub 100m would penetrate the armor of Russian tanks. The MK103 had a higher rate of fire and lower recoil. There was a constant danger of slapping your tail against the tank and auguring as you pulled up from the gun run. Any approach but that sub 100m method, the round bounced off. Some of the 190 groups who worked with the Hs-129 groups used the same method to great effect killing tanks with rockets in the open terrain against the Russians.
You can test this offline with the Ju-87 G2 sub 100 shooting T34 in the side with the twin BK 3,7. Even the BK 3,7 was tested as a single cannon for the Hs-129. The BK 7,5 saw service in limited numbers maybe 25 planes. But, killed all Russian tanks effectively. One sortie against a T34, the 75mm round blew a 3ft dia. hole in it's side. Just too few, too late.
In the MA the Hs-129 B2 with 30mm would become "Commander Mode" target practice for tanks and wirbel fodder while trying to line up for a sub 100 shot in the side. The Hs-129 B3 with the BK 7,5 in theory, could stand off and nail wirbels, maybe.....