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Zotero, Endnote, Mendeley, and Sciwheel work together well. As a result, it is easy for your colleagues to add references to their own citation managers and then export them and send them to you to add to your manager. If you don't want to ask them to set up a new citation manager account, this is a perfectly valid way to collaborate.
Here is some information about transferring references between managers: https://guides.lib.unc.edu/citation-managers/switching
To stay organized, you'll want to make sure you are keeping track of in-text citations another way while you write if you are writing together.