Part of my confusion is I don't know if the transfer would come from outside the US, or if Liberapay's payment processor operates inside the US.
Wells Fargo has a SWIFT code for incoming international wires, but Liberapay does not seem to allow entering a SWIFT code for US withdrawals. And its form for an IBAN transfer doesn't let me select my country.
@Liberapay a thousand stars for this!
@joeyh The change has been deployed, you can try a SWIFT payout now.
@joeyh We're going to modify the form so you'll be able to try with the SWIFT code: https://github.com/liberapay/liberapay.com/pull/1096