Living in Germany I'd rather say both systems are used. 1 best, 5 worst is supposed to reminiscent of school marks and 5 best, 1 worst is reminiscent of Amazon ratings. That's why normally in questionnaires you write next to it what is supposed to be best and what worst. Intuitively I'd indeed choose the 1 best, 5 worst system for surveys in Germany, but it's not consistently used.
A 1/5 would be the highest score, and 5/5 would be the worse score.