Animated Morph Targets? (Blender)

Hey there, I’m trying to get some facial animations working during certain animations in blender, however i’m not sure how to get that to work. I can get my mesh to export as FBX and when I import the model into UE4 I also have all of my morph targets (shape keys) as sliders. However i’m not sure how to actually use these sliders with an animation. Is there a way I can animate the shapekeys inside of the actions i’m exporting in blender? That way in a hitstun animation I could animate a pained expression on the face etc.

Thank you!