When we simulate SolarEdge inverters and optimizers (and we do it a lot here in Israel), we always use the Module Layout tool.
Its also written in the help section regarding SolarEdge architecture :
-the electrical effect has to be evaluated using the "Module Layout" tool, which is adapted for SolarEdge optimizers.
-the shadings option "according to module strings", as usually used with rectangle-strings corresponding to the modules of one optimizer input, is not really suited. It will give under-evaluated Electrical Shading loss.
You can actually also use the Linear Shading option as there are practically no strings in a SolarEdge system (well actually its probably more correct to say that in SE systems we have either 1- or 2-panel string lengths). I havent seen almost no difference in energy production if use Linear Shading option or Module Layout. But I may be wrong here.