Emory makes it easy to double major. However, if you double major and one of them is GBS, study abroad could be problematic. As for pre-law advising, it looks as if it’s one person. Take courses involving research and writing. That would help you, but honestly, law school is a different animal.
Do you really want to be taking courses at Georgia Tech and GBS at the same time? Why not just go to Georgia Tech and their business school?