An error occurs when creating a rig with an add-on to FBX downloaded from Mixamo.

I want to create a rig using the Mixamo add-on. However, automatically created bones have incomplete weights and need to be manually modified.

I manually modified the weights in 3dsmax and exported to FBX. I imported it into Blender and added a rig with the Mixamo add-on and it failed with an error.

The simple workflow is below.

Mixamo on browser

　↓ FBX

3ds max (weight adjustment)

　↓ FBX

Blender (Mixamo add-on error)

It succeeds when I load the DL FBX directly from the browser into Blender and create a rig. I haven't changed anything other than weights. What is the cause of the failure?