Exported fbx and obj files getting hidden faces in substance painter I keep getting these "missing faces" when I export from blender to substance painter. Is this caused because I exported the object in the wrong way or is this an option in substance painter that I've accidentally turned on?

I've checked the normals on blender and it seems to be fine so not sure

I'm not sure if this is an issue with blender or substance painter, so I'm asking here.
It is a mistakes in the normals, is there a chance the legs are scaled in the negative? If yes you should apply the scale and maybe rotation too, then recalculate the normals. If you work in blender 2.8 you can activate blackface culling in the Viewport settings. Or the face normal direction to ease it a bit.