My daughter began as one major, switched, and then switched again. It was not a problem and she graduated in 4 years.
Earning potential is hard to determine because many majors are not job training. Neither one of my kids had majors that led directly to a specific career, and it worked out just fine.
Both of my kids switched intended majors & both switched schools (one because of the switch in major, the other because she wanted a larger school with more academic options). Both finished in four years.
By all accounts (including many of my friends and friends kids;) many kids who start in engineering drop, so this isn’t all that unusual.
Depending on where they have been admitted it may not matter, they just switch majors when they get there…many schools don’t even admit by major, and those that do admit by major or school it will be easier to switch out of engineering than in…
Obviously if they only applied to tech schools this may be different;)
Earning potential would have more to do with the new major she wants to go into. So yes depending on what sje decides. Her decision should really not effect if she finishes in 4 years but keep in mind if she stays with engineering, there are co-ops and internships that could extend her time at college. But she’s getting more training so some kids graduate in 5 years with only 4 counted on campus.