I would think it is easier to get a job in S cal from UMich than it is to get a job in Michigan from USC. Many graduates of U Mich leave the state. SeattleTW has suggested that it will be hard for you to get a job in the US no matter where you go. Econ undergraduates or undergrad BBAs typically don’t have the specialized skills needed to get the visa you would need – at least they would have lower priority than engineers or CS majors who also have a hard time getting the visa.