The closest component we have in OptiSystem would be the S-Parameter component for electrical signals. We are also adding support for optical cross-connects in out OptiSPICE product, where the user can set coupling coefficients and calculate the cross-talk.
If you are interested in specifically calculating the coupling coefficient of crossing waveguides than that application would be best simulated by OptiFDTD.
If you have an article or paper you could link to that discusses the analysis you are interested in, that would make it much easier to determine the correct simulation tool.
Regards