Got busy.  I did try out some Q-Wah options again.  I’m fairly sure that the original chain includes a downswept filter, PLUS a sync’ed flanger.  I suspect the 2nd half provides the upswept WOW.  I couldn’t quite get there in the intial attempts.  I can think of a few more possibilities using both H9’s … but I’d like to avoid that here.

Perhaps faking it with a negative flanger, plus adding 2nd level modulation?  A forced reset of an LFO waveform? Some Phaser configurations are distinctly filter-like. A reversed filter sweep with an expression pedal is doable, as a manual workaround. There are still quite a few more things to try out.  More to come.