Hi Martin - Welcome to the Atlassian Community!
You can't really link projects, but you can link issues between the projects just like you can issues between two JSW projects or two JWM projects. The process is the same.
Can you give more details about what exactly you are trying to do?
👋 Hi there Jira Community! A few months ago we shared with you plans around renaming epics in your company-managed projects. As part of these changes, we highlighted upcoming changes to epics on...
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