The 3D geometry and anisotropic properties of magnetic nanostructures has been found to have a direct impact on their magnetization properties due to spatial coordinates and larger surface areas, which sheds new light on next-generation materials for advanced applications in magnetic energy harvesting. Our work presents novel pathways for the synthesis and assembly of multifunctional anisotropic 3D nanomagnets with various shapes and sizes with key attention to their anisotropic morphologies. We investigated the excellent properties of these new anisotropic 3D nanomagnets for the design of magnetic actuator systems and nanogenerators by embedding the 3D nanomagnets in a piezoelectric polyvinylidene fluoride (PVDF) polymer matrix. The 3D nanomagnets-PDVF composites were found to exhibit the highly electroactive β-phase with enhanced piezoelectric sensitivity. Further, the 3D nanomagnets-PDVF thin films have outstanding magnetic responsiveness and actuation capacity ideal for the fabrication of magnetic nanogenerators. These types of materials have a great deal of potential to generate sustainable alternative energy sources through harvesting and conversion of ubiquitous and residual low-frequency environmental magnetic noise into usable electricity.