Thanks for the feedback, Alex.
The Selection would work in the way demonstrated below
Scene File
https://www.amazon.com/clouddrive/share/fLQYnSlOtdrFkTHFoaMcv1K6LrZADPtPEVQPtrvkWtQ
I used the P.Y here to illustrate the process, check off the Position once it is set.
In a nutshell, the ones that should change are in each MoGraph Selection Tag, and if a change is needed, the next MG Selection Tag get pulled into the Selection field, a keyframe is set and off to the next.
Each selection tag has a complete situation stored and can be used again at any time.
Besides that, you mentioned cross fade, that would need a little bit XPresso. Just to mix from one selection (A) to the next (B) and when this is done (100% B), then swap A out and place C into the mix and got back, etc.
All the best