IME study abroad programs for high school students that run during the school years include attending school in the country where they're living... Rain and all of the NSLI-Y kids started the week after they arrived, 6 days a week and something like 8 hours a day. Some of the classes were in Russian, from the very first - they didn't understand much in the beginning, of course, but by the end they did, and in classes like biology a lot of the terms were similar. She took a great class in Soviet cinema her second semester there, I believe.
She also spent around 4 hours a day in Russian language classes, and since many of the students there studied English she was able to sort of work-study as a teacher assistant in a US History and American lit class, taught in English - I think one semester each. She also took Russian history and geography, which were taught specially to the American students in English (there were 5 of them there in the fall and 2 more joined then in the spring). High school classes in Russia (as in most of Europe, I believe) don't generally meet every day...
She did end up with a school transcript - actually two of them, one in Russian from the gymnasium there and one in English from American Councils, who administered her program. We'll submit that with her college applications, of course, but the homeschooling piece allows us to include things she did besides her work at her Russian high school. For example, she worked through most of Algebra 2 last summer with me (in Tunisia

) because she didn't end up taking any math classes in Russia - she started to, but math is her toughest subject anyway and she found it too difficult to do in Russian.
If your daughter comes with you to do fieldwork for a year, you could enroll her in a local school and also register her as a homeschooler through your U.S. state of residence, which I think would give you a lot more flexibility as far as preparing a college transcript.
Planning way ahead, I know... but that's what we're doing right now, so it's on my mind!