A medieval battle axe with a large double edged 3D model is available on CGTrader for $2.99. Original author: InventiveWorld. Specs: 8072 polys, 6231 verts.
STL (Stereolithography, filesize: 394 KB), OBJ (OBJ, filesize: 7.6 MB), GLTF (glTF, filesize: 2.07 MB), USDZ (USDZ, filesize: 2.05 MB), BLEND (Blender, filesize: 3.55 MB), FBX (Autodesk FBX, filesize: 7.68 MB)