Yes, you can do this using the “Include file from other project” option within the Add Files menu:

One convenient way to set this up if you're planning to use the same files across multiple projects is to organize things as follows:

1. Create a “parent” or source project containing your common files e.g. .bib, .cls, .sty, graphics, etc.
2. In your “child” projects, click the “Upload files” button at the top of the file list panel.
3. Select “From another project”, and navigate to your parent project, and select the file that you need.

You will now be able to use the linked file within your “child” project but you will not be able to edit it. Although linked files in child projects cannot be edited they can be updated (refreshed) if you’ve modified the original copy of the file(s) in the parent project:

• click on the linked file in the child project
• select “Refresh” to pull in the changes.

Note: Any .tex files imported using “Include file from other project” cannot be set as the main file for compiling the child project.