This contribution reports the results of cross-model inheritance for affine candidate derivation. In this test, 4-parameter motion model is converted to 6-parameter affine model by using 4-parameter model formula to generate the motion vector of bottom-left control point. During motion vector derivation for affine sub-blocks, unified 6-parameter affine model is used. Compared to VTM-2.0.1 anchor, the average BD-rate differences are 0.01% in RA and 0.00% in LB, respectively.