Posting anonymously makes this a bit more difficult to answer. I can only offer insight based on U.S. universities.
Here you would "major" in engineering, and "minor" in your secondary field of interest. (A "double major" is another, more intensive option.) It's quite common and not considered a risk to broaden your education and knowledge.
As an example, a family member of mine majored in business and minored in art. His major landed his first municipality job. His minor brought him the opportunity to branch into a more enjoyable area. He's done many art projects for the city, county and state. Here's one.
Yes. He has a sense of humor which helps too. :)