Hi Michael,
You are right, but to be exact, SimShaker Sound Module as addon to SimShaker for Aviators creates the dedicated low frequency effects. SimShaker for Aviators itself provides output to vibrating pads as Gametrix, Realteus or NLR ones via USB.
Yes, I think so.
You probably will find some links below helpful:
SimShaker Sound Module - ED Forums Discussion
Feedback for Flight Simulation – 2020 | Mudspike
https://www.youtube.com/watch?v=tRe2q37KNCk
SimShaker related forum threads
Yes, I think so. There is a demo mode with a limited set of the effects to check compatibility.
Don't forget to disable the Voicemeeter