Unity saves the armature defaults separately from the .fbx-file. If you:

  • Made changes to the armature in Blender, or
  • Use different export settings in Blender And overwrote an existing .fbx-file, then Unity may not use the correct body proportions. To remedy this:
  1. Select your .fbx file. In the Inspector: go to the Rig tab and click Configure.
  2. Scroll all the way down to the Pose-dropdown menu, click Reset followed by Enforce T-Pose.
  3. Click Done!
  4. Optional: open up Pumpkin Tools. Select your avatar and hit reset pose to either Prefab (default pose during importing) or T Pose (good for attaching props)