Mjölnir is a fully PBR textured and realtime-optimized model as seen in the Sketchfab viewer. It comes as both standalone fbx + png files as well as a Blender file with embedded textures. Texture resolutions range from 2k to 512, based on the size of the model parts.

https://sketchfab.com/3d-models/mjolnir-ucac5-1daa3f4ff399437aa61250ef1b202d91