Face animation without bones

How to use in the engine and is it possible to have facial animations without bones? I have several characters whose facial animations are presented in the form of deltamorph animations (several states of the face in the form of deltas to the main mesh) which are a mix of different states in different proportions depending on time
Remaking everything on bones will be problematic and very difficult, one might say from scratch
The engine version is not important, because of the monstrosity of the latest version I think I’ll use 4. I don’t need the features of 5 and 4 is quite enough, and in terms of size and requirements it is much nicer. The only problem is facial animations

You can animate in sequencer using a control rig. Here is a tutorial for setting up a control rig for morph targets.

Morph targets are currently have problems with this system in UE5.5 so I suggest sticking to 5.4 for now.