Unreal 5.3 VR hands for DAZZLE note

A note to myself

To keep up with the OpenXR standard I’m updating the VR hands for DAZZLE: SOLO. I’m looking to modify the new VR template player pawn. In new templates hand the Skeleton has both more bones AND bones for both left & right hands.
My pipeline is to export the template SKM_MannyXR_right hand then import to Blender, import my Dazzle hand mesh, changing my mesh to match the rest position of the Manny hand then import both into Akeystu. Then in Akeytsu I swap the Manny mesh for my Dazzle mesh, thenexport this rigged hand. I noticed that my hand mesh flips down 90 degrees when I skin it in Akeytsu. So I rotated it up 90 then try again. I get it all good to go in Akeytsu but importing my Dazzle hand in Unreal. onto the Manny hands skeleton (SK_MannequinsXR) it flips down 90.

Investigating I realise that if I export SKM_MannyXR_right and reimport to Unreal, its position is wrong to unless I use thee FBX import settings below:
My conclusion is that it may be to do with Unreal 5.3 using FBX version 2020.2 while Akeytsu uses FBX 2016