The requirements for working as an engineer in the U.S. with a foreign diploma will vary depending on the type of work you would be performing and for whom (for example, all 50 States and the District of Columbia require licensure for engineers who offer their services directly to the public, and independent of licensure, a certification program may be required by an employer to demonstrate competency in specific fields of engineering.).
My recommendation is that you talk to someone from an academic credential evaluation service such as Foreign Credentials Service of America or World Education Services. This type of institution is responsible for qualifying academic credentials awarded outside of the U.S. for various purposes, such as university enrollment, employment, professional certification or immigration processing. They would be able to help you understand the requirements that would apply to your case, and if necessary have your credentials evaluated so they can be recognized by licensing and certification boards in the U.S.