I meant to say that if you end making your own weapon meshes (which is usually important if you want to maintain same artistic style across all weapons) or have a teammate take care of it, you might be able to create the meshes such that they retain similar rotational attributes upon importing to the engine.
Not really sure if it can be done within the engine. I’m not very acquainted with the animation side. So someone else might be able to give you a better answer on that.