The Paypal/PaymentGW payment method is used for invoices paid through PayPal and similar online payment services. With it the invoice shows the {Card Company} field, so the card company must be entered in partners — see the prerequisites in Card.
Whether approving the invoice creates a bank transfer pay-in depends on whether the company keeps its accounts in Brix — see Payments against an invoice.
In F1 fiscalisation Paypal/PaymentGW is treated as a transactional payment method. Which protocol an invoice is fiscalised under is described in Sending invoices to F1 or F2.0 fiscalisation.