To further enhance the connection performance of prefabricated composite shear walls from a structural perspective and improve the construction quality and seismic performance of traditional composite shear walls, a new type of composite shear wall reinforced with embedded steel plates between panels is proposed. Following the validation of the rationality of the finite element modeling approach, pushover simulations were conducted on a traditional double-sided composite shear wall (SW1) and two double-sided composite shear walls with embedded steel plates between panels (SW2 and SW3). A comparative analysis was conducted of the pushover curves and displacement ductility of each shear wall, and the influence of different structural configurations on seismic performance was investigated. Subsequently, SW2 was selected for further simulation analysis under different parameters. The findings suggest that the newly developed composite shear walls exhibit a significant improvement in bearing capacity in comparison to conventional designs. Of these, SW3, with its distinctive configuration of concealed steel bracing, exhibits a substantial enhancement in bearing capacity, showing an approximate increase of 19% compared to SW1. The two new composite shear walls demonstrated comparable displacement ductility, suggesting that modifying the arrangement of steel plates does not enhance the deformation capacity of the walls when the steel content remains constant. When the axial compression ratio and the steel content increase within a specified range, the bearing capacity of the new composite walls is enhanced; however, their ductility is concomitantly diminished.