Fe is a neutral, extraverted, INPUT function (as I understand it). When functioning as an INPUT function, it's like a sponge. It merely absorbs without judgment. It could be described as ethical sensitivity (feeling the pain of others, the joy of others, etc.). It may also be called "compassion" (i.e. feeling-with).
Fe is also a decidedly non-neutral, extraverted, OUTPUT function. In this sense, it encompasses the ability of a person (through speech, facial expression, mimicry, gestures, tone, and every other available human faculty) to affect others ... generally by "pushing their emotional/ethical buttons" to achieve the decidedly subjective aims of the person who's deploying Fe as a means of changing the world (even if that change is something as trivial as just changing the "mood" of one person, i.e. cheering them up). Needless to say, Fe (when well and subtly deployed) can do a lot more than that, on occasion, and may affect a great number of people, but that's how it works as an extraverted OUTPUT function as I understand it.