See the following paper.
"The S-probe-a new, cost-effective, 4-gamma method
for evaluating multi-stage amplifier stability".
Wang, K.; Jones, M.; Nelson, S.;
Microwave Symposium Digest, 1992., IEEE MTT-S International , 1-5 Jun 1992
Page(s): 829-832 vol.2
Such analysis is used for PA design which have multiple stages. :P
Supplement.
In the above paper, author implemented this method using legacy touchstone netlist, so many of you might not be able to understand netlist.
In this netlist, we can calculate four impedances, Zs, Zs11, Zs22, Zload at just one s-para simulation.
Here to realize this calculation, author are using 10 ports for sp-analysis.
But if you can permit two simulations instead of just one,
you can do same calculation more easily.
For example, if you use Spectre of Cadence, insert current source for evaluation of impedance using ac-ana, then using Ocean, switch this current source to evaluate impedance for another side.