If it would be a static mesh you have to do this :
If it's a skeleton mesh , it is not that easy , then it's better to do the flipping in your 3D app.
Is it a prop or cloth in CC3 , then you can edit the normals in CC3.
![https://forum.reallusion.com/uploads/images/6b9df7df-52bd-4830-8f70-ae7f.jpg](https://forum.reallusion.com/uploads/images/6b9df7df-52bd-4830-8f70-ae7f.jpg)
To get sure it's a normals problem , activate this to see you normals :
![https://forum.reallusion.com/uploads/images/743214ab-082b-4df3-abbd-1794.jpg](https://forum.reallusion.com/uploads/images/743214ab-082b-4df3-abbd-1794.jpg)
You also can try to recompute tangents.