Png and Jpeg on different accounts.

I suppose you should put the assets, in one account. Physically you will need to establish 2 tax forms but with the same content. If you do this, separate rigorously the assets.

Probably a bad idea. It's one thing to have two different accounts for, say, images and video and audio, but pngs and jpgs? Those are both images. You might be setting yourself up for having both accounts blocked, depending on the content. In addition, I don't understand why having two accounts for different image file types is of any advantage. I suspect it would have little impact on your sales.