Display custom message on invoice if VAT was deducted

Hi,

I use plugin WooCommerce EU VAT Assistant to calculate the VAT for when the customer is from a different EU country (needed by European law) and I use your plugin to generate the invoices. The law of some EU countries states that if the customer uses their VAT number during checkout, the VAT must be deducted (EU VAT Assistant plugin handles this), but also the invoice must state that the is 0% VAT and there must be one sentence in the footer stating that the customer has to pay the VAT themselves.

Do you have some kind of action or filter hook which I could use to include a custom message into the footer and the 0% VAT on the invoice?

Thank you.