Polycristalline materials with inter-granular phases are modern composite materials extremely relevant for a wide range of applications, including aerospace, defence and automotive engineering. Their complex microstructure is often characterized by stochastically disordered distributions, having a direct impact on the overall mechanical behaviour. In this context, within the framework of homogenization theories, we adopt a Fast Statistical Homogenization Procedure (FSHP), already developed in , to reliably grasp the constitutive relations of equivalent homogeneous continua accounting for the presence of random internal structures. The approach, combined with the Virtual Element Method (VEM) used as a valuable tool to keep computational costs down, is here successfully extended to account for the peculiar microstructure of composites with polycrystals interconnected by thin interfaces. Numerical examples of cermet-like linear elastic composites complement the paper.