racemenu , change npc face

[HighMood77]

(( for the love of god )) can some body tell me what should i do to change npc face ???? here is what i did.... i export the head data from racemenu in old skyrim (( i have to have it side by side with SSE since the SSE racemenu didn't have sculpt option !!!!!! )) so .... after i export facegen ( dds & nif ) files i head to CK & create ESP plugin to change Sylgia face , then i hit CTL+f4 to export Sylgia facegen from CK ......... so now i must replace the facegen from CK with facegen that i export it from racemenu (( transferring the blocks from one .NIF file to another )) so i must do this step with NifSkope program but i don't know how ...... the mod ( NPC Nif Merge ) do this step automatically , but since there is no hope to convert this mod to SSE version so what should i do in NifSkope to replce the files ??????
2 years & no one give me answer to this question !!!!!!!!!