Unfortunately we do not support combining student journals from one class to another.
Items are stored in the class where they were uploaded and approved by a teacher. It is possible to download items one by one from one class and upload into another class.
To add items from a class into another class, you'll need to download each item from class A, then upload the item into class B.
Here's how: Find the item to move in Class A and click the three dots in the bottom right of the item > click download item. Then, go into class B and upload the item and tag to the correct student. This will move their item from class A to class B.