Have you tried this query:
project = ABC and issuetype = Epic or parent in (ABC-1, ABC-2, ABC-3)
^ This gives you all the Epics within a Next-Gen project plus all the child issues of a set of Next-Gen Epics which you define.
Parent is used here rather than "Epic Link" as it's Next-Gen.
The ABC-* references each Epic singularly, providing the children of each. This is useful if you only want to locate a selection of Epic's children via issue search.
If you just want all Epics and their children which are displayed on the roadmap then you could use:
project = ABC and issuetype in (Epic, standardIssueTypes())
^ Or you can customise the issue types if you don't want all standard types - for example to just receive Epics and Stories:
project = ABC and issuetype in (Epic, Story)
For JSM June Challenge #2, share how your non-technical teams like HR, legal, marketing, finance, and beyond started using Jira Service Management! Tell us: Did they ask to start using it or...
Connect with like-minded Atlassian users at free events near you!Find an event
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no Community Events near you at the moment.Host an event
You're one step closer to meeting fellow Atlassian users at your local event. Learn more about Community Events