The regulatory law is the administrative regulation for § 26 StVO (= Road traffic regulations), in particular "VwV I. S. 5 zu § 26 StVO".
Instead crossings for pedestrians at traffic lights must be marked using dashed lines ("Fußgängerfurt").
This situation occurs in all of Ingame Germany.
Example:
Game version 1.39.2.4s
Combined semaphores and zebra xings illegal in Germany ;[07/01/2021 23:04:55] (sec-0001-0005);-576.125;29.2329;-16277.4;-0.0101174;-0.501292
Always Reproducible
Win10 64bit

Reallife example: https://www.google.de/maps/@53.5458419, ... 312!8i6656
-> Ped crossing at traffic light marked with dashed lines while ped crossing without traffic light marked with zebra.