Tried on 5.1 and 5.2
Exported the LyraStarterGame/Content/Characters/Mannequins/Animations/Manny/MM_Walk_Fwd.uasset
MM_Walk_Fwd.glb (20.4 MB)
As far as I can tell, you cannot roundtrip any Manny animation? Let me know if you find one you can export and then reimport. Maybe I am missing a configuration setting?
On import it says:
LogInterchangeEngine: [Pending] Importing
LogInterchangeEngine: [Pending] Importing
LogInterchangeEngine: Error: [Failure] Import Done
LogInterchangeEngine: Error: [Failure] Import Done
Thanks for your help