Currently a pull request from Bitbucket can only be added to the Remote System Links section automatically when the pull request is created, and there isn't a way to add a link to a pull request manu...
In addition to adding multiple pull requests to "Remote System Links", it would also be beneficial if manually uploaded commits from different repositories can be grouped together under repository specific headings in the "Review Materials" section.
Link to a existing related feature request - https://community.smartbear.com/t5/Collaborator-Feature-Requests/Git-Repository-Name-on-review-with-multiple-git-repository/idc-p/244537#M1057