Macroscopic anisotropy in polycrystalline materials is of key interest since it may help filling the gap between randomly oriented polycrystals like ceramics and single crystals. Non-destructive X-ray Computed Micro Tomography (XCMT) is a necessary step towards the full control and modelling of such anisotropy, beyond the standard scheme of interfaces. To ascertain this progress, XCMT is applied to 3D mixtures of ferroelectric and dielectric oxides processed by Spark Plasma Sintering (SPS). In such conditions, not only is this anisotropy seen in the overall dielectric parameters but it also shows up in ferroelectric properties. Experimental macroscopic parameters are linked to the 3D morphological anisotropy of individual MgO inclusions induced during SPS.