You can make some changes in Bulk across multiple items in a module, using the "Bulk Actions" button at the bottom of the register view.
Different actions are available in different modules, but they all work in a similar way.
Because 'Bulk Actions' edit multiple items at once, you will need to be in the 'Staff' or the relevant module_manager group to have permissions to make these changes.
Members can use 'Bulk Actions' to manage their 'Collections' (the A, B, C tabs).
First find the content you want to transfer using the search options. If you're reassigning content, you might want to search by Assignee (or equivalent). In Documents, you might search by Approver or Editor.