2d normal map inverts highlight/shadow workaround help

New to unity! when I add 2d normal maps to my main player animations and then flip the scale to walk left, the map inverts all of the shadows and highlights. Is there a simple way to fix this? The only Idea I have came up with is to make a second normal map with the channels inverted to reference while my player if flipped. But where I am stuck is how would I make the change to the inverted map in the importer in my script?