Importing animations with shape keys from Blender

I am relatively new to Blender and Unreal, so I’m still trying to figure out the proper workflows. I have run into some difficulties related to character animations, however.

I created and rigged the following simple character:

After that, I created some simple idle and walking animations:


These animations are stored as separate NLA tracks, each corresponding to a different Action.

Exporting these to an FBX file and importing them in Unreal seems to work fine with the following settings:

However, to make the cloth animations a bit more realistic, I’ve defined some Shape Keys on the mesh of the cloak of my character:
image

I tried to animate these to go along with the ‘Run’ animation, and was only able to push them down to a separate NLA track:

This shape-key animation is now not tied to any of the separate other Actions. In my FBX export I disabled ‘Geometry > Apply Modifiers’ and in the Unreal FBX Import, I enabled ‘Mesh > Advanced > Import Morph Targets’. Although the shape key animations are correctly imported for the ‘Run’ animation, they are in fact imported with every animation. This is understandable, as I have never ‘tied it to’ a specific animation Action.

I have the feeling that I am not approaching the animation workflow in the correct way, but I found it difficult to find any resources explaining how to do it properly. Can I get some suggestions?

You need to flag and export them as custom animation curves for it to work right.