Is it permissible for a woman in full hijab to be part of a mixed da'wah team (men and women) that engages in da'wah in more than one language?

If a woman's participation in Da'wah work does not lead to suspicious intermingling, and there is no fear of temptation, and a preponderant benefit is found, then there is no harm. However, it is preferable for men to be separate from women.