We are currently using EFT for our UK based vendors. We want to extend our usage of EFT to Euros and USD vendors. How do I go about this? What payment file format do I need ?

Depends on the bank. Ask them

what’s type of bank account ? Iban ? Or not in sepa zone ?

Our bank is HSBC, so I think it's Swift code rather than IBAN for USD? Not massively clued up on this field so any help is appreciated.

If you have United Kingdom localization , you have this template : HSBC UK International Be sure to enter either Account Number or IBAN and Bank Code or SWIFT/BIC Code in the Entity Bank Details to prevent validation errors.