Entropy analysis is closely scrutinized for unsteady mixed convection in magneto-hybrid nanofluid (Cu–Fe $$_3$$ O $$_4$$ –water) flow over an inverted cone surrounded by a porous medium. The mathematical model comprises nonlinear, coupled partial differential equations. The numerical solutions of constitutive equations assisted by related initial boundary conditions are obtained by an effective finite difference method. The specified ranges for active parameters are: $$0\le \varphi _\mathrm{hnf}\le 0.04$$ , $$0\le M\le 5$$ , $$0.5\le K\le 3.5$$ , $$0.6\le \hbox {Gr}\le 1$$ and $$0.1\le \hbox {Br}\Omega ^{-1} \le 0.4$$ . The impact of various parameters arising in the constitutive flow model on the virtual flow parameters is analyzed carefully, and the outcomes are illustrated graphically. Also, steady-state entropy production and Bejan lines are plotted for various active parameters. In addition, the physical quantities, i.e., heat transfer and momentum coefficient, are scrutinized for various parameters and the outcomes are displayed in the tabulated form. It is witnessed that heat transfer rates improved incredibly with growing estimates of hybrid nanoparticles volume fraction. The Nusselt number enhancement of Cu–Fe $$_3$$ O $$_4$$ –water hybrid nanofluid are 0.53%, 0.76%, 0.95% and 1.1% corresponding to volume concentration of 1%:4% with a difference of 1%, respectively. The theoretical measurement of skin friction showed a maximum enhancement of 0.25% at a volume concentration of 1% compared with Fe $$_3$$ O $$_4$$ –water nanofluid. Moreover, the momentum and heat transport coefficients are compared with those of natural convection and the result showed that heat transfer coefficient attains higher rates in mixed convectional flow compared with natural convection.