We have a group of about six people who will be accessing the material. Can multiple people have access to the same material?
Real-time collaboration is not built-in yet, but if you use relative paths to link your photos and store both project file and photos in a location that is accessible from multiple devices (e.g., a network shared folder) then everyone can open the project.
Note that Tropy does not resolve sync conflicts automatically, so you must be careful not to work on the same project simultaneously.