You can create an epic or a story in one circle with the initial user story and then delegate the epic/story to another circle for further refinement and implementation. The team in the circle delegated from will still be able to follow the state of the epic.
The epic/story seen from both circles
The state, title, user story and description will always be the same seen from both circles. If e.g the user story is modified by the team in one of the circles, the other team sees the changes as well.
Users from both circles can enter epic/story comments, and the comments can be read and replied to by both teams.
The delegated epic/story can, however, be assigned to different releases in the two circles. It can have different assignment to user/team and it can have different value and effort estimates.
Activity logging for when delegating and changes are made is also done across both circles for the delegated entities.
What you can do with the epic/story in the circle delegated from
The team in the circle delegated from will usually enter the user story text before the epic/story is delegated to another circle. They may also place the epic/story in a release to indicate the expected deadline. And they could enter value estimates for the epic/story.
When the epic/story has been delegated, the team in the circle delegated from can still follow the state of the epic/story. Users will be able to change the user story and description, but will usually not do this, as they have handed over the epic/story to the other circle team.
If the epic had child stories or epics, these are moved to the circle delegated to. They are not visible anymore in the circle delegated from, and it is not possible to create new stories or epics below the delegated epic.
The epic/story can be planned to a release or sprint if needed but not to kanban. This limitation is based on the theory that any delegated work will be tactically implemented in the circle delegated to.
Attachments can be added to, edited and also deleted from the epic/story and this will be reflected in the circle delegated to.
What you can do with the epic/story in the circle delegated to
When the epic/story has been delegated to another circle, this is where it is handled from now on.
Any stories or epics below the delegated epic are moved to this circle. The team can add more child stories and place these in sprints or kanban for implementation.
Attachments can be added to, edited and also deleted from the epic/story and this will be reflected in the circle delegated from.
The team that is on the Circle where an item has been delegated to, may want to turn down a delegation for one reason or another. This is done from the context menu which is accessible via right click or context menu. It will result in that item being deleted from the Circle.