Here are my picks, if only my schedules allow:
Fri 28.9. 16:30 - FIfFKon18 conference "Brave New World": some promising talks on privacy and GDPR on the program
Sat 29.9. 10:30 - Discussion and project presentations "Datenschutzfreundliche Smartphone-Anwendungen ohne Kompromisse?" (part of FIfFKon18 conference workshops)
All aforementioned events are free, but require sign-up. And these are, indeed, all in German language (I intend to post summaries here, if I find the time).
Please say hello if you see me around!