The problem that we are facing is that in some projects you could have different fields, that are not allowed in your new project. So if you move a story, it won't have the allowed values for the new project.
You could move your story with an sql query, by simply changing the projectID, areaID and iterationID fields in dbo.WorkItem table. If you have any values that are different in your target project, you could also change them with a query (for example status field).
Note that this will work only for stories without relationships, tasks, attachments, acceptance criteria and so on.
If you want to move a story (or other workitem type) with all it's data you could use the attached script.
Note that on row 17 is the select statement. Now the script will only move your Feedback items.
Also on row 164 there are several things that you need to change:
Declare your projectIDs here:
DECLARE @oldProjectIDtoMigrate INT = 1;
DECLARE @newProjectIDtoMigtare INT = 2;
and also declare your new project area id (all items will be moved to one area)
DECLARE @newProjectAreaID INT = 1;
Please, before doing this on your live database be sure it's tested and working on test environment, because this might change the data in your project that you don't want to.
If you need further assistance, feel free to contact us at any time.