Pre-med chem majors will have issues since they can’t fulfill reqs out of the US. But a regular Chem major? Surely there are approved programs.
My D is in a sequential sort of STEM major and needed particular courses in a particular order. She’d wanted to go to a Spanish speaking country for her semester abroad but that came off the table because none of those programs had 2 necessary courses her major department would accept and that she needed to take THAT semester. But a few countries did so she chose one of those and had a great semester abroad and came back with everything she needed to continue on with her major peers.
How to make it work is a question your D needs to ask her major department and study abroad office. Just because other kids don’t do it doesn’t mean it cant be done. She just might have to choose from a much smaller number of specific programs.
Worst case, she might do a study-domestic program in another part of the US. But I just googled “study abroad Chemistry” and got a bunch of program results.