Possible to tell engine to use custom class over default class?

Trying to override functionality of BonePose.h and BoneContainer.h with a derived class.
Engine built from source, plugin made at project level. Have tried testing plugin at project and engine level.
I’ve seen:
though GameEngine and any other reference like it appears to be a variable within engine.h.
I’ve also seen class redirectors, which I attempted:


But it’s still calling on BonePose.h, rather than my own UniversalBonePose.h

Is it even possible to override engine classes in this fashion?

One note, I tried that class redirector in both BaseEngine.ini where engine version class redirectors are, as well as within the project’s DefaultEngine.ini