Mortph a single low poly to multiple high poly blend shapes


I a making assets for use in a game engine and i have multple blend shapes on a high poly mesh that map to different features on the model. Now i have made i low poly for the base state of the highpo mesh wich i baked onto. I would like to know what is the most efficient way to get the low poly to match the different blend shapes.
As an example, a character mesh who’s nose can change shape would need a morph and a new baked normal to blend between in game in order for the nose’s geometry to always match its bake.