My hunch is that she'd be alright with this. Somehwat relatedly, there's a Dr. Axel Rauschmeyer (also from Germany) who talks about JavaScript and is almost always referred to as "Dr. Axel". Then there's Dr. Tedros Adhanom Ghebreyesus, who is quite correctly addressed by his title and given name, "Dr. Tedros", omitting the patronymic components. And no, you usually do not quote a person's full name unless in court as you'd usually leave out the middle name(s). But in the end it's up to Dr. Hossenfelder I guess.
Quite. Many colleagues I know want to be addressed by their first name and almost shy away from being called professor. I myself feel awful ramming my titles down others' throats, and basically never correct people unless it's relevant -- it's very easy to make yourself look like a jerk...
