This feature is currently in development and is expected to be released at the beginning of August.
Permissions to administer Swanly are assigned on the Global level. To edit this permission you need to be a Jira Administrator. Find the scope of the permission here.
Add permission to Administer Swanly
Go to the Jira > Settings > System > Global permissions
On the bottom of the page, in the Grant Permission section, select in the Grant field the Administer Swanly and then assign to the desired group
Click on Add button
Remove permission to Administer Swanly
Go to the Jira > Settings > System > Global permissions
In the list of permissions find Administer Swanly together with a list of groups to whom this permission is granted
Click on Delete in the group you want to remove permission from
Confirm removal of the group from this permission
Read more about global permissions in Jira in the Atlassian documentation.