EPR (Einstein-Podolsky-Rosen) steering is a special quantum phenomenon, which allows one side of the entanglement system to steer the other side, and has potential application value in one-way secure quantum network communication, quantum secret sharing and other quantum protocols. Based on the continuous variable (CV) bipartite entanglement swapping, covariance matrixes are reconstructed by asymmetric modulation or noise addition into one of the swapped mode. The EPR steering characteristics between two parts of the final output are analyzed and compared. The characteristic difference of the bipartite EPR steering between the two modes and the relationship of the EPR steering parameters with the classic modulation factor and the size of the noise are studied. The theoretical research results provide a feasible reference for the realization of the security of quantum communication.