Prof. Dr. Schwarz in Reinbek near Hamburg is a renowned surgeon in Germany who does mastectomies and hysterectomies for guys the doctor and the hospital are recommendable.
Then there is the Florence Nightingale hospital in Düsseldorf .
I also know that the team around internationally renowned Dr. Lidl near München does hysterectomies specifically for guys, usually directly in combination with metoidioplasty as far as I know though.
Dr. Beyer in Kaiserslautern does hysterectomies too, then there is the GFO hospital in Troisdorf but I haven't heard much about that last one yet, haven't talked to anyone who's been there.
Hope that's helpful! If you have further or more specific questions, as I have undergone that surgery in Germany, feel free to PM me.