Is there a brush shape in editor?

I really would like to know, where is exact positon of brush in editor when I dig or rise a terrain - in my case, there is no visible brush shape (not even in tree painter, grass,…).

Is this normal or I should somewhere turn on brush shape visibility?

No, unfortunately there is no visualization for the size of the brushes in the Terrain Editor, but I am pretty sure some feature requests have already been submitted regarding this issue. Hope you can manage without it.