Sprite - Normal Map ShaderGraph

I download a Sprite Normal Map ShaderGraph from the the Unity's GitHub repository here: https://github.com/UnityTechnologies/ShaderGraph_ExampleLibrary/blob/master/ShaderGraph_ExampleLibrary_Project/Assets/ShaderGraphs/Sprites/Sprite-NormalMap.ShaderGraph

When I use this ShaderGraph and set the GameObject scale.x to -1, the light starts displaying upside down. I duplicated the normal map shader and set the "Two Sided" property to true so that the flipped GameObject could be seen and also added a Flipbook node with the height set to -1 and although the sprites are being affected by the light in the right direction, they aren't displaying properly. Telling me a way to do this would mean a lot to my team since artist has already drawn all the normal maps one by one and the appearance of the game depends on it. Here's a gif if anyone is interested: https://gfycat.com/FamiliarKindlyBug

Thanks for your time.