github: how to reference an issue in a commit from a different repository?

I have two repositories:

• Repository A
• Repository B

I also have a project:

• Project X

This Project X has Repository A and Repository B as linked repositories.

In Repository A I created several issues:

• Issue 1
• Issue 2
• Issue 3

All these issues are appearing on the kanban board of Project X. When I now do a commit on Repository B:

closes #1

The commit wont get linked to the Issue 1 of Repository A. Can I configure the project in a way that I can create such references from commits from different Repositories? Or do I use this wrong?

#1 refers to issue 1 in this repo.

username/repoA#1 refers to issue 1 in username's repoA.

org/repoA#1 refers to issue 1 in org's repoA.

You would use either of the last two options

See Autolinked references and URLs: Issues and pull requests.