Create Cut Fill between design models

The create cut fill volume tool can be very useful but I was wondering if there is any way/workaround to use it between design models. To my mind there is no way without changing the feature definitions of the elements for one of the models to the existing volume option (or another one other than design) which would be messy.

I want to ideally avoid having to go through the process of starting to create formation terrains for everything if possible.