Actually you would enter it twice. Once as self employment income, so it populates schedule C and then as income as TTLina described to exclude it.
What is very important is, that you do not need to pay into both social security systems, as Germany and the US entered into a Totalization agreement. As a self emplozed person in Germany, you are only required to pay into the German System. You can get a certificate of coverage from them and avoiud paying SE taxes in the US. See here> https://www.ssa.gov/international/Agreement_Pamphlets/germany.html
