Letter of Recommendation for a University Freshman?

I would still use a professor. Go talk to one that seems approachable and give them a list of your accomplishments. They will write a general one, but at least it is a professor. Your foreign language teacher may not be in the subject area you want to study, but I bet they know you better. Have you thought of having your advisor write one? I would talk to a professor, many are willing to write one even if they don't know you. They don't need to know you