i'm trying to implement this shadow technique. Anyway, looking around for some code examples, it seems that i have to create a copy for all the shaders to insert custom matrix multiplication required by PSM.
So my question is:

is it possible to modify only the modelviewprojection matrix ( with the needed concatenations for PSM ) to avoid modifying all the vertex shaders?

Is it possible to create a modelviewprojection matrix to transform from 3D world coordinate to NDC ( normalized decive coordinate ) including the perspective divide??