Our DS didn't do it, but his friend did. At his college for the scholars program they are expected to do an internship. She did it in France as an international relations major.
For AFROTC you have to time it right because you need the support of the command and out of sight is out of mind when it comes to meeting boards. She did it in her spring semester of her jr. yr. Again for the AF, you meet your AFSC board Jan. of your jr yr. So, in her case by the time she did this all of her paperwork for the board was already submitted...no harm no foul to her AFROTC and future AF career.
The problem with foreign exchanges is they do not have ROTC for the most part.
Your child should talk to unit and ask them directly if they will support this, if they have supported in the past, and if you can speak to cadets/mids that have done it.
AGAIN...this is why you should always request one on one with the units when you do that college tour. They can provide you with information that is pertinent to your situation.
Commands love it when they get these requests because their job is to groom future leaders. Part of that is dispelling myths by educating them regarding ROTC at their college. An ROTC unit at PSU is not necessarily going to be the same as the ROTC unit at UMiami. They all have the same foundation of ROTC, but leaders do impact the unit based on the needs of the unit.