We are planning to create a project in Jira to have all Test cases from all projects. That would be the centralized repository for test cases. We need to link this test case to a user story in the other project.
Thanks for your inquiry, but before we reply, could you clarify if you're using Zephyr for Jira (native to Jira) or Zephyr Standalone?
We dont have this option for Zephyr for Jira currently, but we are working on a feature called TEST REPOSITORY which should make this possible.