@sindarin, I don't really think Skrill support that kind of exchange even if you look at it from their TOS. you can check and check article no 11.5 and the first paragraph. You can only do that which you got approval from them and it is not as the usual exchangers we know.
https://www.skrill.com/en/siteinformation/terms-conditions/
https://www.skrill.com/en/siteinformation/terms-conditions/