Thumbnail can be fix by (Quote from UDN) "adjusting OrbitYaw of the ThumbnailInfo for the +X-facing skeletal mesh"
Persona Editors can be fix by (Quote from UDN) "setting SkeletalMesh->SetHasCustomDefaultEditorCamera(true) and computing a corresponding view transform to set DefaultEditorCameraLocation, DefaultEditorCameraRotation, DefaultEditorCameraLookAt and DefaultEditorCameraOrthoZoom."
We need to verify if those are the correct place to make this change. We also have to do a similar fix for staticmesh editor.
import a skeletalmesh with force front x option enabled.
The thumbnail will render on y axis and skelmesh editor will default to y axis.
Its probably the same for staticmeshes
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-113217 in the post.