Hello @Louis Bode - Welcome!
When you say "project teams tab in the stories" are you referring to a specific dropdown field? If so, the answer is yes: a Jira Administrator can go to "Jira Administration (settings icon top right) > Issues > Custom Fields" and find the particular field and add an option to it.
I'm not sure how the project roles would appear on a story as those are used to designate users within a project.
Hope this helps