This study numerically examines the heat and mass transfer characteristics of two ternary nanofluids via converging and diverging channels. Furthermore, the study aims to assess two ternary nanofluids combinations to determine which configuration can provide better heat and mass transfer and lower entropy production, while ensuring cost efficiency. This work bridges the gap between academic research and industrial feasibility by incorporating cost analysis, entropy generation, and thermal efficiency. To compare the velocity, temperature, and concentration profiles, we examine two ternary nanofluids, i.e., TiO2+SiO2+Al2O3/H2O and TiO2+SiO2+Cu/H2O, while considering the shape of nanoparticles. The velocity slip and Soret/ Dufour effects are taken into consideration. Furthermore, regression analysis for Nusselt and Sherwood numbers of the model is carried out. The Runge-Kutta fourth-order method with shooting technique is employed to acquire the numerical solution of the governed system of ordinary differential equations. The flow pattern attributes of ternary nanofluids are meticulously examined and simulated with the fluctuation of flow-dominating parameters. Additionally, the influence of these parameters is demonstrated in the flow, temperature, and concentration fields. For variation in Eckert and Dufour numbers, TiO2+SiO2+Al2O3/H2O has a higher temperature than TiO2+SiO2+Cu/H2O. The results obtained indicate that the ternary nanofluid TiO2+SiO2+Al2O3/H2O has a higher heat transfer rate, lesser entropy generation, greater mass transfer rate, and lower cost than that of TiO2+SiO2+Cu/H2O ternary nanofluid. (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic). (sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic) (sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic). (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic) (sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic). (sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic) (sic), (sic)TiO2+SiO2+Al2O3/H2O (sic)TiO2+SiO2+Cu/H2O, (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic). (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)Soret/Dufour(sic)(sic). (sic)(sic), (sic)(sic)(sic) (sic)(sic)Nusselt(sic)(sic)Sherwood(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic). (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)Runge-Kutta(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic). (sic)(sic) (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic). (sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic) (sic)(sic)(sic)(sic)(sic). (sic)(sic)Eckert(sic)Dufour(sic)(sic)(sic)(sic), TiO2+SiO2+Al2O3/H2O(sic)(sic)(sic)(sic)(sic)TiO2+SiO2+Cu/H2O. (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic) (sic)TiO2+SiO2+Al2O3/H2O(sic)TiO2+SiO2+Cu/H2O (sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic).