Hi, I've seen Bendy Bones to be flexible when animating. Since a bone can be used to deform a mesh, is it possible to capture the mesh deformation with bendy bones into Shape Keys so it can be exported to a Game Engine (as I believe bendy bones are a Blender construct only)?
Shape keys from my understanding are the same as having two keyframes in the timeline, of an animation. The model or armature changes from one position to another. With keyframes you can adjust the timing easier, with the shape keys you can control the timing with a driver.
You can animate your bendy bone scenario and export the animation to Unity or else where.
Take a look at animating-first-person-character-weapons-in-blender, here in the later lessons JL talks about exporting animations to Unity.
Hope this makes sense!
The problem with Shape Keys, is that they move Vertices in a straight line between two positions. While a Bone can rotate and make an eyelid fold over an eyeball naturally, a Shape Key would make it go in a straight line, intersecting the eyball.
I hope this is somewhat understandable.