Import it to MWO as a Netlist => Spice netlist (*.cir, *.ckt, *.lib, *.sp) & then
use in the schematic...
If you wnat S-parameter file then setup the linear simulation if it is a Diode or FET, BJT then setup the bias & simulate...
Finally export the file as Output file in Touchstone S-parameter file format...
If you have difficulties upload your spice model here...