  The ultimate objectives of ongoing and upcoming neutrino experiments are the
precise measurement of neutrino mixing parameters and the confirmation of mass
hierarchy. The systematic inaccuracy in the cross-section models introduces
inaccuracy in the neutrino mixing parameters estimation. It is important to
secure a large decrease of uncertainties, particularly those relating to
cross-section, neutrino-nucleus interactions, and neutrino-energy
reconstruction, in order to achieve these ambitious goals. In this research
article, we use three alternative neutrino event generators, GENIE, NuWro, and
GiBUU, to analyze sensitivity studies of T2HK, DUNE, and combined sensitivity
of DUNE, and T2HK for mass hierarchy, CP violation, and octant degeneracy
caused by cross-section uncertainties. The cross-section models of these
generators are separate and independent.
