I'm also curious. I checked my own preorder and was only given the option to edit the shipping address. I saw no option to edit the payment method.
If I had a preorder that I was planning to cancel, I am sure I could ask someone to reimburse me and then change the shipping address. However, I just don't see how the potential risks would be worth it.
Of course, things may be different if you are able to change the shipping address and payment method, but that would mean that the person taking over the preorder would have to be willing to give you their credit/debit card number.