Yes, you can do this for any imposition type. However, please note that this is a two step process. After opening your document, tick the Std. Marks and Grow Art check-boxes. You might like to test the default grow-art value, increasing or decreasing as necessary. It is important to choose an Output Sheet that is a little larger than that imported, so the new enlarged document will fit! When you are satisfied that the new document has the necessary bleed, close this pdf and open it in Pyxis Imposed. Then choose your desired imposition type, including 4-up Imposition.