As much as I love a good kula, I was never able to find a loophole for shaking hands with women. And belive me I tried, but no where could I find any posek that gave a green light on this one. Not MO, not anyone.
Sitting on a bus, even between two women, can be mitigated by holding a sefer (or like the Rebbes do when walking in the street, holding a cane). But to shake hands? Looks like this one’s a closed case.