if you want something to be displaced using an angle, you can do this using a fixture
choose fixture > advanced > choose an axis
then your inputs are radial, circumferential (angle in rads/degrees) and axial
if that doesn't fit the bill, please elaborate on your application and attach a screenshot of what you're working with, how you're trying to move it and how you expect it to move.
do you want to rotate about the red arrow? if so, the method I described above is the way to do it. I would probably apply it at the very end face on the right that is normal to the arrow.
the same method works if you want to fold the bellows out. you would just create an axis like the long arrow that you have in your screenshot. my experience is that it would be somewhere away from the center of the model so that you get the right curvature.