As noted above, Brown might be a good option to look into because students (all of them, not just engineering) don’t have to declare their major (concentration) until end of sophomore year. Plus the Open curriculum helps with exploration, even within a heavily-structured program like ABET-accredited engineering.
Here is the link to Brown’s engineering programs . It looks like all disciplines take ENGN 30 and 40 in semesters 1 and 2, and then start to get more specific in sophomore year. But you can change to and from any major at Brown at any time, if you have the needed classes or the time to take them. And no secondary admittance requirements, which also helps with flexibility .