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Coupling between fast magneto-acoustic and Alfv\'en waves can be observe infully ionized plasmas mediated by stratification and 3D geometrical effects. InPaper I, Cally & Khomenko (2015) have shown that in a weakly ionized plasma,such as the solar photosphere and chromosphere, the Hall current introduces anew coupling mechanism. The present study extends the results from Paper I tothe case of warm plasma. We report on numerical experiments where modetransformation is studied using quasi-realistic stratification in thermodynamicparameters resembling the solar atmosphere. This redresses the limitation ofthe cold plasma approximation assumed in Paper I, in particular allowing thecomplete process of coupling between fast and slow magneto-acoustic modes andsubsequent coupling of the fast mode to the Alfv\'en mode through the Hallcurrent. Our results confirm the efficacy of the mechanism proposed in Paper Ifor the solar case. We observe that the efficiency of the transformation is asensitive function of the angle between the wave propagation direction and themagnetic field, and of the wave frequency. The efficiency increases when thefield direction and the wave direction are aligned for increasing wavefrequencies. After scaling our results to typical solar values, the maximumamplitude of the transformed Alfv\'en waves, for a frequency of 1 Hz,corresponds to an energy flux (measured above the height of peak Hall coupling)of $\sim10^3$ $\rm W\,m^{-2}$, based on an amplitude of 500 $\rm m\,s^{-1}$ at$\beta=1$, which is sufficient to play a major role in both quiet and activeregion coronal heating.

Fast-to-Alfv\'en mode conversion mediated by Hall current. II Application to the solar atmosphere