As a Cross Border Trade (CBT) seller, you must register for a German VAT ID if your sales to German buyers exceed 100K Euros in a calendar year across all sales channels.
For example, if your annual sales on eBay is 80k Euros and 30K Euros on different selling platforms, your total sales would be 110k Euros. This means you are required to register for a German VAT. In order to comply with the VAT policy, you must:
Display a valid German VAT ID in the “Business Seller Information” in My eBay
Display your company name or an individual’s name on “Business Seller Information”
File monthly and annual tax returns, and pay your taxes
Your company’s name or individual’s name displayed must match the VAT ID owner found on the EU VIES website.