Flipped normals display darker

Hey guys I have problem with normals imported from Maya. As suggested I reversed my flipped normals in Maya and imported then back to SP, but it didn't solve issue entirely, as now instead of transparent, they display in darker manner. When I apply any material on it, it appears matt and I can't find any solution for it online. Maybe someone faced issue like that before? Thanks in advance.

here's screenshot of what I'm talking about