For small planets orbiting within the habitable zones of their host stars, multicolour validation via photometric transit observations offers an efficient alternative to prioritize targets before intensive radial-velocity follow-up, thereby expanding the sample of habitable-zone exoplanets amenable for atmospheric characterization. In this study, we validate two exceptional habitable-zone Transiting Exoplanet Survey Satellite (TESS) candidates, orbiting around M-dwarfs, as genuine planets, precisely determining their transit and physical parameters. We perform Bayesian model comparison by jointly fitting multicolour light curves from TESS and ground-based follow-up, including observations with HiPERCAM at the 10.4-m Gran Telescopio Canarias. Our approach uses wavelength-dependent transit depth variations and precise transit geometry to reject false positives. We validate TOI-2094 b and TOI-7166 b as two new benchmark temperate mini-Neptunes. TOI-2094 b (1.90 $R_{{\oplus }}$) orbits its M3V star (V = 14.4, d = 50.22 pc) with a period of $\sim$18.79 d, well within the habitable zone ($\sim$0.98 Earth insolation). TOI-7166 b (2.39 $R_{{\oplus }}$) orbits its M4.5V host star (V = 15.8, d = 35.24 pc) with a period of $\sim$12.92 d, placing it near the inner edge of the habitable zone ($\sim$1.93 Earth insolation). Statistical mass and density estimates suggest that TOI-2094 b may be a volatile-rich planet, such as a water world or a gaseous planet, and is less likely to be rocky, while TOI-7166 b is likely to be volatile-rich. Both planets are of great interest for detailed atmospheric characterization with the James Web Space Telescope and future extremely large telescopes, which requires further precise mass measurements.