Create morph targets in Unreal by using Cinema 4D and the Pose Morph tag. This video will show you how to setup your model and poses and then create an asset that you can keyframe.
https://www.cartandhorse.studio/
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00:00 - Intro
00:27 - Unreal Overview
02:17 - C4D pose morph
09:16 - Unreal morph targets
18:07 - much obliged