I'm not quite clear what you mean, but if you want to add a new product that starts as a clone of an existing product, we don't currently have a way to do that, though that feature request is on the wishlist.
That said, if you're adding a series of new products, once you finish adding a product and reach the button codes screen for that product, if you click Add Another Product from there without going back to Seller Admin first, the next new product would start off as a clone of the last-added product.
