If you clone an issue in Jira Cloud with Epic Clone a dialog will be displayed where you can make your configuration of the cloned issue and its child issues. On this page it is explained what you can do on this dialog. Let's assume we want to clone this issue with Epic Clone:
It contains 3 child issues and 2 linked issues. Child Issue 2 contains 3 sub-tasks. If you now select the three dots → Clone Template you will get the clone configuration dialog.
Dialog if target project is a team-managed project:
Dialog if target project is a company-managed project (Epic):
Target Project: Select the target project for your clone. You will only see projects in the select list you have access to and where you have create permission.
If you change the target project, it is immediately validated whether the issue type of the source issue is available in the selected target project. If it is not available this error message appears
Summary: Set the summary for the cloned issue. The summary of the source issue is displayed by default.
Epic Name: Epics in company-managed projects have the epic name field. If you clone an epic from a company-managed project, you can set the epic name field for the cloned epic. The epic name of the source epic is displayed by default in this case.
Labels: Existing labels of the source issue will be displayed by default. You can select additional labels from the existing ones or add additional new custom labels. The labels inserted in the field will be added to all created issues.
Components: In company-managed projects components can be defined and selected in the issues. If you clone to a company-managed project, you can select components to be set from the existing components in the target projects. This selection list will be populated every time you select a new target project. If you select a team-managed project as target project, the field disappears as components aren’t available in team-managed projects.
Assignee Options: Choose from the following options for the assignee field:
Clone Assignees: Assignees from source issues will be copied to cloned issues. Please note that this is only possible when cloning within same project. If you clone to a different project the issue will be unassigned.
Assign parent issue to me: Cloned parent issue will be assigned to user executing the clone. If you don’t have assignable user permission in the target project, the issue will be unassigned.
Assign all issues to me: All cloned issues will be assigned to user executing the clone. If you don’t have assignable user permission in the target project, the issues will be unassigned.
Due to a technical limitation, we currently can’t check for assignable user permission for other users than the current user. As soon as this will be possible, we will add a user picker for the assignee field, so other users can be selected as assignee.
Fix Versions: In company-managed projects releases can be defined and selected in the issues fix version field. If you clone to a company-managed project, you can select releases to be set in the fix version field from the existing releases in the target projects. This selection list will be populated every time you select a new target project. If you select a team-managed project as target project, the field disappears as releases aren’t available in team-managed projects.
Due date: Select a due date to be set.
Parent Link Options: If the source issue you want to clone has a parent link set, you can choose whether you want to clone that parent link to the new issue or not. This field only appears when a parent link exists.
If you click on next, you will get to the second page where you can configure which child or linked issues you want to clone with the source issue.
Child Issues
Choose for child issues which ones to clone together with the parent. Issue type, key and summary are displayed in the checkbox list.
Child issues can be issues in epic for epics or sub-tasks for other issues.
There will only be those issues selectable which have an issue type available in the target project. If you can’t select some of them from the source issue, their issue type is not available in the target project you have chosen on the screen before.
Linked Issues
If the source issue has other issues linked to it, they will be displayed in a checkbox list on the right side of the dialog. On top, you can choose from three different clone link options.
Clone Link Options:
Clone links only: This means that the target issue will be linked to the same issues than the source issue
Clone linked issues: Linked issues to source issue will be copied as well and linked to the target issue
Don’t clone links: Nothing happens with links. They won’t be considered at all for cloning
Below the options you find the checkbox list of linked issues. Like for child issues only those links will be considered which are checked in the list.
By default, the last option is selected and if that is the case, no issues are selectable in the checkbox list.
If you have finished your settings, click on run to start the cloning.
Result Screen
During cloning you can see the progress and how, step by step, the issues are cloned. On the left, the source issues are displayed, in the middle you see a spinner when cloning is not completed and a 
icon if the cloning is done. On the right side you see a link to the cloned issue and can directly navigate to it (link opens in a new tab).
On top you see the issue that is currently in progress either for cloning, or setting a link to the new parent issue.
When cloning is completed, you can quickly navigate to each source or target issue by using the displayed links.
