Without workflows or scripts, is it possible to send payment vouchers from Bill Payments in bulk (not using the EBP bundle)? If I check the Send Transactions via Email preference in the Vendor record and use the Pay Bills page, that might work. But it also means that all other Vendor transactions such as Vendor Bill and Bill Credit will be automatically sent to the Vendor if there's an email address.

not without scripting or workflow. Though if you have dunning module you use that to send bulk email to vendor/customers based on the transactions