Comment by throwup238

Most electrical engineers use “reference designs” published by the IC manufacturers to design their PCBs, although any open source commercially available design can act as a reference. They essentially copy the schematics from the PDF (or import if file formats/converters allow), ripping out whatever they don’t need, then reroute the PCB using their layers.

In some cases, when their PCB fab layer stack up is similar enough to the original board, they can go a step further and copy paste most of the PCB into their design so that any signal integrity work carries over. Realistically this is only really practical for low speed designs but still useful for a whole class of electronics.

I don’t use KiCad but software like Altium support modular schematic sheets and PCB rooms so theoretically it can imported into that (since KiCad’s format is open source S-expr)