Some people have used a range of flexible mounting solutions, some for dashcams some for action cameras / regular cameras.
https://www.amazon.com/gp/B07GQZ4QZ3
If you are not interested in the GPS features ( which are handy for setting time not least if RTC battery go south ) you can always disable it / any form of watermarking in the footage.
Just know no one will ever judge you by the GPS speed of your camera,,,,, Oo no, they will resolve 2 things in your video footage, go measure the distance in between them, and then take the time from your video it took you to cover that distance, use verified math to extrapolate speed up to mph, and so get a even more accurate speed measurement, one that will fly in court.
If you are apprehensive about sticking camera to windscreen, many cameras today come with a clear static sticker you can put on the glass, and then stick your mount / camera to that.
Flexible mount can be a problem, even if it is stiff enough to not introduce jello in the driving footage, then as seen in so many times in crash videos when it happen it will be forced to tilt upwards and so after the accident all it will film is sky if you dont aim it back down.