We have pushed our solution of the FBX problem in Blender to production. All animations should be in T-pose in Edit mode now.
Please bear in mind that this is a temporary solution. There may still be minor issues that pop up (animations may have bones with abnormal rolls).
In a few weeks, we expect to release a new skeleton that more fundamentally solves this problem with an add-on that makes re-targeting a drag and drop process for users.
The new Gen3 T-pose can be found here on our downloads page.