Summary

This Kb covers how  user stories from one instance ex: https://ABCD.atlassian.net/ can be linked with user stories on another instance https://XYZ.atlassian.net 

Environment

Jira Cloud

Solution

Issues can be linked between two Jira instances using Application Links by following below steps:

Note: Jira Admin access on both instances is required to perform the below steps.

1. In the Source instance go to Jira Settings > Products.
2. Select Application Links from the left-hand menu. 
3. Click on Create link
   
4. Copy and Paste the URL for the destination instance
   
5. Press Next, and follow the instructions
6. Once application link is created between the two instances, while creating issue links, you should now see the option to choose which instance the Issue is in - local, or otherwise(remote) as shown below