No – there is not a way to bulk create D2L grade items.
The best way to quickly create grade items within D2L is to do so from the Manage Grades tab of the Grades area of the course. When creating grade items, you can use the Save and New button to quickly create an additional grade item (if you are building many of the same type of grade item).
You can read more about using the D2L Grades area in our Grades guide.