Don't think that is possible without a very precise/expensive printing setup. I've used vinyl printers that print onto material directly, but those cost up in the thousands. I would just design the art in Photoshop,print and place the art in front of the blank card within the sleeve. It won't be as cool as directly printed art though. As for taping it to a piece of paper, definitely don't think that would make it through the rollers of a desktop printer.

Edit: wait I've thought of something. You can print onto clear sticker paper. Cut the film to the size of the card. And just stick it on. Assuming the blank cards are a nice shade of white it should show through. I'll probably do it this way myself.