The demand for advanced data storage is skyrocketing due to unprecedented growth of digital information, energy constraints, and cybersecurity concerns. We propose a scalable, robust, and cost-effective technology for the production of materials through the knowledge-based design of high-entropy MXenes, streamlined synthesis of MXenes functionalized Potassium Sodium Niobate(KNN) ceramics by controllable energy-efficient self-propagating high-temperature synthesis, and development of multilevel encoding technique leveraging different discretized signal intensity and temporal levels. For the first time, we propose a sustainable, clean and high-tech approach to production of HEMXenes added KNN for optical data storage, optical switchers and anticounterfeiting technologies. Integrating luminescence with photochromic properties presents an advanced approach for high-density, multi-level, and rewritable data storage. We provide a rational route from basic research to engineered applications.