Student or Learner
Usually, Chinese students like to call teachers from the US or the UK or other foreign countries "foreign teachers", or sometimes "international teachers". And I've also heard of "native-English teachers"...
I personally feel these some kind of improper, but I don't know what on earth is the right expression.
So dear teachers, what do you prefer us to call you?
I remember hosting a seminar in Shanghai a few years ago. Most of the students chose to call me an international guest lecturer/educator. Personally, I don't mind as long as it's not derogatory. You should ask your instructors about their preferred designation. International Instructor sounds appropriate.