You can use a csv import for the data and then manually copy the other stuff. Or you can look into the JSON option:
If you are growing and scaling your usage, it might be a good time to look into using server. Cloud has a 25g limit on storage and about a 1 gb cap on the JVM.
No...unfortunately. You might want to consider cloning the two cloud instances to staging environments on a server deployment, then merge the two cloned instances into a single server deployment. You could use project configurator to assist with the merge.
To jump onto Ryan's answer, it is due to the lack of support for single project import into Cloud that would require you to import the issues individually as he suggested.
For more information or for alternative solutions, you can have a look at How to migrate projects from one JIRA Cloud application to another.
Finally, we do have a feature request below, that you can vote on and watch for any updates or changes:
Let us know if you have any questions or trouble with anything we've gone over so far.
Hey Community mates! Claire here from the Software Product Marketing team. We all know software development changes rapidly, and it's often tough to keep up. But from our research, we've found the h...
Connect with like-minded Atlassian users at free events near you!Find a group
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no AUG chapters near you at the moment.Start an AUG
You're one step closer to meeting fellow Atlassian users at your local meet up. Learn more about AUGs