Is it possible to add both nation rules and continent rules at the same time?

[codingandgamingwithadam]

Is it possible to add both nation rules and continent rules at the same time as when I added nation rules adding continent rules was greyed out.

I basically want to make changes to some of the nation's player/registration rules etc but then also want to bring back the European cup winners cup and potentially create a European/World super league too just for the fun of it.