In this study, \(\textrm{Co}_{2}\) VPb is analyzed as a multifunctional material, confirming its stability in the cubic phase and robust half-metallicity with 100% spin-polarization at the Fermi level and a total magnetic moment of 3.0 \(\mu_B\) per formula unit. The analysis of the density of states identifies Co and V atoms as the main contributors to magnetism, while the electronic band structure shows a metallic majority and a semiconducting minority channel with an indirect gap of 0.743 eV. Additionally, the material displays a stable mechanical structure, excellent thermal stability, and strong ultraviolet absorption with high infrared reflectivity. Notably, it demonstrates a large Seebeck coefficient and a maximum thermoelectric figure of merit of approximately 0.95 at 300 K, indicating significant potential for sustainable energy technologies.