The only thing really available is a source control system wherein that multiple people have access to all the same files, but the file becomes locked when a person opens it - meaning two people can’t edit or view a single file at the same time.
UE4 has two plugins already, Perforce and SVN, for source control. A plugin is being developed, but it’s only being worked on by one person, and it’s been in development for about a year and a half as a side project as a means to enable real-time editing with multiple users for levels and blueprints, it is not ready though and I do not expect it to be for many many months.