Is there a way to link cloud issues from different sites?

[Becky]

Current Scenario:
We have an enterprise account with multiple products and different sites. For example:

• Jira Software at x-site.atlassian.net
• Jira Software at y-site.atlassian.net

How can I link an issue from a project on x-site to an issue in a project on y-site?

All sites are hosted on cloud.

[Trudy Claspill]

Hello @Becky 

Take a look at the answer on this post. I think it addresses your question.

https://community.atlassian.com/t5/Jira-questions/How-can-I-refer-to-an-issue-on-a-different-Jira-Cloud-Instance/qaq-p/1338977

[Becky]

The link in the answer of this topic is directing to a server documentation, there’s no documentation on it appointing to connection between cloud to cloud instances 

[Trudy Claspill]

https://support.atlassian.com/jira-cloud-administration/docs/use-applinks-to-link-to-atlassian-products/