The easiest way would probably be to create an example scene in Marmoset, which fully supports anisotropic reflections through the use of a flow map ; and then post that example on the Unreal forums to see if someone experienced with Unreal materials and shaders can help you recreate it.
There's a few ways to fake it, what material are you trying to make? There's examples of hair shaders, and brushed metal can be done with a normal map.