Hard to say what really goes on inside the old pedal!
Usually there are two ways you can build a replica: either you have the original and know how to do "surgery" on it to get all the guts secrets of it…or using your ears is the simple way to go. Path #1 is the best.
I'm only guessing what you may try here, in Vsig.
The PhaseShift gives you a choice of poles #, from 2 to 50. These are the all pass filters.
You may try using 2 Phase modules w/2 (or 4 poles) each, connecting them in series. Use an LFO thru a MIX module (as in the TC 1210 preset) or thru a SCALE module (as in the 3_D Phase Inverter preset) to create phase inversion, before connecting it to the PhasShift MOD input.
You may also try having a 2 ch. mixer before the phase shift to create feedback…helps THAT woosh a lot. Experiment placingthe 2PhaseShift in series OR in parallel, or having 2 in series processed by 2 in parallel or the opposite of it. Try using more poles in each module. Then summ all Phasers thru a mono mixer. You have to try it all to make your ears realize what the sound is.
Also try using some filters to cut out some low end before the phasers….
There's a lot you can try.