https://blendermarket.com/products/instant-impostors–one-click-impostor-generation-eevee

     With Instant Impostors, users can automatically convert any mesh into an optimized low-poly impostor, massively increasing performance in large-scale scenes. Using advanced shader-based rendering, the impostors display a detailed representation of the original mesh, utilizing 3D parallax, self shadowing, and translucency to further replicate the detail of the original object.  This addon is compatible with EEVEE only, and cannot export impostors to other game engines or programs. Additionally, animated impostors are not currently supported.