Does the robot need an operating manual in German?
Yes. The operating manual must be available in the official language of the Member State in which the machine is placed on the market.
A manual available only in English does not meet this requirement in Germany, Austria and Switzerland.
Important for imports: whoever translates takes on responsibility for the accuracy of the translation. For safety-relevant information this is no formality – settle in the contract who produces the translation and who is answerable for it.
Who is answerable for what in a direct import is clarified in Who is liable if I import a robot directly from abroad?.