I have the same problem! I need to be able to charge 7% on digital products and 19% on other products. This is not possible on Squarespace - thus making it non-compliant with the German Tax regulation.
Furthermore, gift cards receipts have to display the VAT at the moment of sale in case the single VAT rate is applied to all the products. So the gift cards at the moment not displaying the VAT are not compliant with the German Tax regulation either.
It would be great if this problem were addressed asap.
Thank you!