So part one is easy. Can I press B and stop the evolution of a Machoke into Machamp for example?
Part two is like this. Traded Pokemon that require hold items to evolve such as Seadra use up the hold item when they evolve. Well, if you can stop the evolution, what happens to the item of that Pokemon. Seadra is evolving, I press B to stop it from doing so, does the Dragon Scale stay or is it gone?