Thank you @Roy_Wierer.Seda145 i will this later if i really decide to put this into the marketplace. For now and my own needs i will try to do this within ZBrush and merge the text with the models.
Still needs more testing to only use polypaint. Not sure what it is but the GPU gets really hot even the GPU-RAM usage is very low if i only use this high dense polypainted models. Feels like this way i somehow break the LOD system of nanite or the render pipline cant handel the fast informations.
I guess to test this i need to do 2 scenes with high poly models and the same models but a way nanite can change the topo. Really not sure at the moment if this was an accident or this simply is to much what i try do. Just makes no sence to me right now.