Hi, I have a big accent too. I don't care
I live here for only 3 years, and I am 1l. I didn't really study English before I came here. I don't think I will ever be able to speak without any accent.
Some proffessors will help you b/c you are foreign student. Most of them will not.
I wouldn't worry about your accent at all, there always will be people who think you are stuped just because you don't speak well. Ignore them. However, most of those people don;t go to law schools.
Worry about your grammar and your writing. Take classes, buy some books and study now, when you still have time.
I know several foreign people who went through law school and they are doing pretty good now.