Four new molecules namely BsubPcM1, BsubPcM2, BsubPcM3 and BsubPcM4, are designed by substituting different electron withdrawing groups as acceptor groups at boron atom (axial substitution) of subphthalocyanine i.e., cyanide (BsubPcM1), 1,2,3,4,5-pentafluoro-6-metoxybenzene (BsubPcM2), 2-methylisoindoline-1,3-dione (BsubPcM3) and 1-methyl-4-(prop-1-yn-yl) benzene (BsubPcM4). Photovoltaic parameters are estimated through DFT by employing selective method B3LYP. Frontier molecular orbitals, Density of states, Optoelectronic studies, and transition density matrix calculations are employed to characterize the chemical reactivity, charge mobility, open circuit voltage and maximum absorption of all designed molecules. The reorganization energy calculations proposed that the electron mobility for BsubPcM1 (0.0093), BsubPcM2 (0.0077), and BsubPcM4 (0.0095) is smaller than BsubPc-Cl (0.0097). Furthermore, BsubPcM1 and BsubPcM4 carry the least value of hole reorganization energy (0.0042) and (0.0039) respectively which is less than the Parent molecule BsubPc-Cl (0.0044) that symbolize the magnified hole transfer. Amongst all, BsubPcM3 has maximumr wavelength of absorption (577.9 nm) with minimum bandgap (2.46 eV). The results show that axial modification of Boron Subphthalocyanine Chloride molecule is a promising pathway for the development of modified efficient D-A type materials for photovoltaic applications.