Thanks for reaching out to the Adobe Stock community.
Yes, you can purchase an Adobe Stock asset under the Extended license and can use it in Germany and The United States.
Adobe Stock subscriptions and licenses for individuals may be purchased online in the US, Canada, Mexico, the UK, Ireland, South Africa, New Zealand, Australia, Japan, Russia, Brazil, Netherlands, Norway, Sweden, Denmark, Belgium, Switzerland, Finland, Luxembourg, Germany, France, Italy, Austria, Spain, Portugal, Greece, Poland, Czech Republic, Bulgaria, Estonia, Latvia, Lithuania, Hungary, Malta, Romania, Slovenia, Slovakia, Cyprus, and Hong Kong.
However, the pictures do not have any geographical license border.
Additionally, you may also refer to the licensing terms and restrictions of Adobe Stock: Stock Licensing & terms FAQ: Where can I find the terms and licensing information for Adobe Stock?
Hope this information helps!
Feel free to update this thread in case of any additional questions.