Several years ago ResearchGate had this feature, but it never worked properly. Usually, the bibliographic data in the exported list were rather incomplete. Later they removed this function completely. The problem with such features seems to me that RG is a private company and has to finance its programming work somehow. On the other hand, it is free for users.
I have added your question to https://www.researchgate.net/post/What_improvements_would_you_like_to_see_for_ResearchGate.