STMesh SKMesh Smooth Group different

Hello, I have the following problems in importing my skeleton mesh object. After importing the skeleton mesh object, it seems that the smooth group is not displayed correctly, but the same static mesh object is completely correct in the same project. And I checked that the smooth group information of the skeleton mesh object is also correct when exporting FBX. When importing, I found that the import type was also selected Import normals and tangents

Sorry, My English is poor, you can see the picture below
this is stmesh

this is skmesh

thank you!

is that because of the texture lose its accurancy? I was encountered with kind the same problem before, can you share your fbx mesh maybe? so I have have a look at that