Many banks utilize on-line wire systems. Unless you are dealing with the new international remittance transfer rules, I'm not sure what other notices would fall under E-Sign to process a wire transfer. As far as what needs to be included in your terms and conditions agreement for on-line wire transfers, that is really a question for your legal counsel. You need a binding agreement that specifically sets forth the commercially reasonable security procedures that will be in place.
The opinions expressed are my own, take them or leave them.