Additional assignment-related features and issues within Microsoft Teams for Education
Hi Daniel,
I would like to suggest you download the rubric, edit it via the desktop Excel client, save different copies, and upload them in a new or existing assignment draft to use.
Reference: Create and manage grading rubrics in Microsoft Teams
Besides, during adding an existing rubric in a new or existing assignment draft, you may directly edit the rubric.
Hope this helps.
Best Regards,
Hugo