How can i copy a group set to a new library in Endnote 21.5?

I have a EN library with ~5000 references with pdfs. I am writing a manuscript with colleagues and need to export ~100+ for this project which have been carefully categorized into a group set with groups based on topics. Some references are in multiple groups. How can I take that group set and copy it into a new library.

Please don’t tell me to use “smart groups”. There must be a way to copy the group set structure from one library to another.

I don’t see a way to save the group set. I cannot export it. Or drag and drop it into an empty library. I can drag and drop the references, but then I will need to recreate the group set.

Thanks in advance.