Q: can I ship photo book directly to Germany?

No.  The shipping address for any print product must be in the same country as the billing address of the credit card used to purchase the print product.

And besides, you wouldn't be able to check to book for errors before sending it along to the recipient. Occasionally there are printing errors, bad color, etc.

With that in mind review the book according to this Apple document, Preview a print project in Photos, iPhoto, or Aperture to avoid issues - Apple Support and save the pdf file to compare with the printed copy when it arrives.