@Jurijsk I previously reported the same thing via the smiley feedback icon and receive an email that this is being worked on. But so far it has not changed for me.
As a workaround I created a new Bing entry based on the one that was created automatically and changed the language to EN from DE. I then set this new entry as my default.
This is definitely not the solution and it needs to be possible to have the automatic one act the way it did in legacy Edge.
In the interim it would be good if we could at least edit the automatically generated one.
