I made this model in zbrush completely from scratch so it might not have UVs, this model have 6 million ActivePoints so obviously I have to retopologize this model in 3ds max to reduce its polycount, how will I be able to bake this character's normal to the 3ds max ones (which will be UV layout differently). I am really confused, please help!

Usually I do the inverse, I take low poly object from 3ds max (UV unwrapped), add detailing in zbrush and export normal map.

Best Regards,