Defect chemistry plays a crucial role in the properties of potassium sodium niobate (KNN)-based ceramics. The preparation method can significantly impact the types and concentrations of defects present in the material. Cold sintering, involving sintering the material at low temperatures with the help of a transient phase under axial force, increases KNN ceramics' density and suppresses the volatilization of potassium (A-site) elements, compared to conventional sintering. In this study, we investigate the crystal phase, microstructures, and dielectric permittivity, in a wide temperature range for donor and acceptor doped (K0.4675Na0.4675Li0.065)(Nb0.92Ta0.08)O3 (Ca2+ and Fe3+ respectively) prepared via cold sintering-assisted route. Furthermore, impedance spectroscopy was specifically harnessed to determine the electrical conductivity and identify the concentration of defects for doped and undoped KNN. The results of this study indicate that cold sintering leads to the formation of ceramics with a lower concentration of charge carriers, in particular, oxygen vacancies. Additionally, a comparative study of conventional vs. cold sintering is focused on elucidating the electrical and ferroelectric properties, which can be attributed to the distinct sintering mechanism. These findings suggest that cold-sintering-assisted production could be a novel method for tailoring the defect chemistry of KNN-based ceramics for specific applications.