We report intriguing characteristics of light-induced and tunable shift currents in Bi_(1-x) Sm_x FeO_3 (0.00≤x≤0.18) films, reflecting contributions from opto-electronic processes through structural phase evolution. Optical reflectance spectroscopy reveals asymmetry in sub-bandgap and direct-bandgap transitions, indicating phase-induced energy-level shifts. We demonstrate how visible-light dramatically alters transitions involving O-2p ↔︎ Fe-3d exchange interactions, and how continuous-wave illumination selectively excites charge carriers in Bi1-xSmxFeO3, leading to spatial separation into localized and band-like states upon optical transitions, thereby laying out all-spatial control routes to shift photovoltaic currents.