This is in reference to UE-19861, where morph targets can display really bad normals. FBX’s can only store one set of normal data from the base mesh. I’ve contacted Autodesk about FBX’s storing a morph’s normal information. But it doesn’t sound like that’ll be in a new FBX plugin anytime soon.
An alternative fix that is DCC driven, is to possibly allow users to manually import morph targets outside of the initial skeletal mesh.
Users would export/import to Unreal their base skeletal/static mesh from the FBX as usual. But from the DCC they would also export the morph target with the unique normals each to a separate FBX. In UE4 they’d then import the morph target FBX’s with the unique normals one by one (or batched).
It’s suboptimal, but it’d be a reliable method and option for those wanting to import unique normal data for each morph target.