Incorrect animation import from Blender

Hello, I’m having a problem with hand and finger bones in an animation exported to FBX from Blender and imported from that FBX into Unreal. Any parameters I set do not help:

  1. If I switch to “Convert to Scene”, there are always dancing fingers in some part of the animation.

  2. If I switch to “Preserve Local Transform”, it has good rotations, but bad hand scale.

  3. If I disable “Convert to Scene” and “Preserve Local Transform”, there are different results related to the transformation options I selected when exporting to FBX file:

  4. Z up, X or Y forward - we will get the same result as when “Convert to Scene” is turned off.

  5. Z forward, X or Y up- we will get incorrect dancing fingers at the beginning of the animation and at the end.

  1. X or Y up, X or Y forward - we’ll get good finger animation, but the right hand bone will always be offset from the default position.

My main rig:

I use the UEFY plugin to create the rig, but I guess it doesn’t matter since only the deformable bones are exported anyway, and those are just abstractions and controllers.

I’ve tried clearing and applying transforms, changing the scale to 100 when exporting to FBX, but none of that helps. I wouldn’t be posting here if it weren’t for one thing: this only happens in Unreal Engine. If I export that FBX back to Blender it’s fine, if I export that FBX to Unity it’s fine too. So, I think it’s a Unreal problem related to FBX import (maybe it’s the transition between transform spaces, I don’t know). I am attaching FBX files with the mannequin and animations inside. You can try importing these animations into Unreal or Unity, or try importing back into Blender and see the result.

ThirdPeson_Rig_X-Forward_Y-up.fbx (2.0 MB)
ThirdPeson_Rig_X-Forward_Z-up.fbx (2.0 MB)
ThirdPeson_Rig_Z-Forward_Y-up.fbx (2.0 MB)

Anyway, I hope this post will be useful for me and all the people who are animating in Blender and will wait for the result. Thanks in advance for the replies.