In German Kompetenzgerangel means a situation between either persons or organisations (typically: government agencies, or departments in a company) where there is a lack of clarity about competencies of the individual parties, and parties try to grab competencies or responsibilities that others claim for themselves.
I tried to find an expression for that in English which has, like Kompetenzgerangel, an air of ironic criticism of the (childish, immature) behaviour of those involved. However, dictionaries so far have not helped me. I found one suggestion: bickering over competencies but I do not know if I can trust the source.