Here’s how I did it;
Create new project as First Person Template (Blueprints)
Make it so no one else can see your First Person mesh
Blueprints > MyCharacter > Components > Mesh1P > Rendering > Only Owner See (checked)
Add your 3rd Person mesh:
Blueprints > MyCharacter > Components > Add Component > Skeletal Mesh (I named mine “Mesh3P”, as there is already Mesh1P for the first person mesh)
Mesh3P > Mesh > Select “HeroTPP”
Mesh3P > Rendering > Owner No See (checked)
Remember to position the mesh nicely so that it has the correct rotation + position to align with the First Person Mesh.
Enable self-view of 3rd Person shadow, even though 3rd person mesh is hidden from self;
Mesh3P > Lighting > Cast Shadow (checked)
Mesh3P > Lighting > Cast Hidden Shadow (checked)
Animate the the 3rd Person Mesh
Mesh3P > Animation > Animation Mode > Use Animation Blueprint
Mesh3P > Animation > Anim Blueprint Generated Class > ASP_HeroTPP_AnimBlueprint
The “ASP_HeroTPP_AnimBlueprint” blueprint comes with the free Animation Starter Pack from the library. I did try it with the default TutorialTPPAnimBlueprint but ended up with a static shadow following me everywhere with his arms locked out to the sides.