In posBoss, you can Duplicate an item once it has been created. We don't currently have an "option set" feature that updates multiple mods on items at the same time.
However, the Duplicate function is quite powerful, and not only copies the optional and required mod groups... it also copies:
So the idea is to get one item set up right and then get duplicating by pressing the drop down on the done button or the duplicate option at the bottom of the item screen.
The item will copy and all you need to do is change the Item and button names and you're away!