You can zero-rate the purchase when you are registered VAT EU member. You can check it on this page. If your number is valid - create your shopping account here, and complete your delivery and company address. Don't forget to fill the Vat No. field (eg. FR957082893 ). Your account will be assigned to 0% VAT enabled purchases.
In all other cases you will get invoice with the 23% VAT added.
f the customer purchases from a country outside the EU, the customer will NOT pay Polish VAT. When the goods arrive to the home country the customer will be charged the national VAT instead via customs and excise.