It already is apparently: https://en.wikipedia.org/wiki/Hate_crime#Germany

The German Criminal Code does not have hate crime legislation, instead, it criminalizes hate speech under a number of different laws, including Volksverhetzung. In the German legal framework motivation is not taken into account while identifying the element of the offence. However, within the sentencing procedure the judge can define certain principles for determining punishment. In section 46 of the German Criminal Code it is stated that "the motives and aims of the perpetrator; the state of mind reflected in the act and the willfulness involved in its commission"[44] can be taken into consideration when determining the punishment; under this statute, hate and bias have been taken into consideration in sentencing in past cases.[45]