That's okay, Biotic Shepard has other tricks up her sleeve.
...Let's not even get into Engineer Shepard. Engi!Shepard is strong against shields. 99% of Master Chief's health is shield. Without it, he's a one-hit wonder.
Well, the kinetic barriers in ME and the energy shields in Halo don't necessarily operate on the same principals. Something that weakens or drops a barrier that uses tiny mass effect fields won't necessarily work on something that uses a magnetically-contained plasma field.
Also, the Chief is still completely covered in half a ton of power armor that even armors the black bodysuit underneath. At a minimum, he's going to be just as strong without his shields as Shepard would be. If Shepard forgets to wear his/her helmet in a combat zone (a distressingly common occurrence in some games), the Chief is even more protected.
Depends on if Shepard is a vanguard or an adept or a sentinel, tbh. If she's a sentinel then Chief is in trouble and if she's a vanguard Chief will never see her coming because she can basically teleport using Charge.
And that'll do.....what? The Chief has enough armor and physical augmentation to survive a 2 kilometer fall under Earth's gravity. Getting hit by a Charge will send him flying due to the mass negation, but it'll probably do little more than bruise and disorient him from the flip. Assuming he even goes flying that hard, since we never really see Shepard punching 1000 pound enemies and there has to be an upper limit to how much mass the power can negate.
The only reliable way to take down a SPARTAN-II in full MJOLNIR armor is to use powerful weaponry. The only way for Shepard to win would be to bring an overwhelming amount of firepower that can destroy the shield and armor. Of course, Shepard doesn't get to bring his/her biggest guns unless the Chief can bring HIS biggest guns. Such as a Spartan Laser that would likely go straight through Shepard (kinetic barriers don't do squat against focused light).
