As the global pursuit of sustainable power intensifies, thermoelectric materials show promise in energy conversion uses such as high-temperature power creation and waste heat recapture. This study explores the high-temperature performance of Holmium–Antimony–Tellurium (Ho-Sb-Te) materials and how they perform together compatibly. It also expertly deposits them using pulsed electrodeposition onto Bi2SbTe3, Zn2Sb3, and SiGe substrates to optimally control stoichiometry. The thermoelectric properties studied were Seebeck coefficient, electrical resistivity, thermal conductivity, and the figure of merit (ZT). These properties were carefully measured experimentally within the 300–1250 K range. Simulations were conducted within Ansys Workbench to assess several compatibility factors. Efficiency greatly improved as a result of increasing operating temperature, and the leg-pair (2 pairs, 3 pairs and 4 pairs) results show peak values of 23.68 %, 36.24 %, and 46 %, respectively. SiGe had the highest compatibility factor, in the range of 1100–1250 K, and this observation confirmed that it is well suited for high-temperature power generation. N-type materials, as a class, exhibited superior levels of thermal and charge transport, thereby rendering them ideal for efficient heat management. This work guides the selection of materials for the improvement of thermoelectric power generation, optimizes leg geometry, and synthesizes techniques. In the future, we will explore composite materials. We will also evaluate the thermal cycling reliability of these materials for real-world deployment.