Use Engineering Flex G19V600000AA0E9 with 45R flash and 004D language pack on V600 go to the last page and download the TRIPLETS_G_0B.09.35R, there is a 0015(simp.chinese) language pack in side

0014 = UK English, Traditional Chinese
0015 = US English, Simplified Chinese
0016 = US English, Traditional Chinese
0024 = UK English, Simplified Chinese
004D = UK English, Simplified & Traditional Chinese