The proforma invoice without VAT can be issued for customers resident in non-EU countries and for customers resident in EU countries with a VAT number.
On the checkout page, in the "Indirizzo di fatturazione" section, tick the "Acquista come azienda (Sarà emessa una fattura)" option and fill in all the required fields: Ragione Sociale, Partita Iva, etc.
Payment must be made with PayPal; after that you can request to issue a VAT refund.
Specify below the order number for which you wish to receive a VAT refund.