How about an emote on the fly ": nod"? I see /e works, but that changes your default chat type for that tab. Is there something like ";" and ":"?
You must not use a blank after the ":" when using an emote in the Enhanced Client. Type ":nods" instead of ": nods". Same with whispering.
I feel ": " (colon space) should work the same as it does in Classic when you're in Classic speech mode. It would make the transition between clients easier and help if you're like me and use both clients often. I always go ": " then stop, backspace, and type again when I'm using EC. It's annoying enough that I made some pre-recorded emotes and put them on a hotbar, whereas I've spent the last 9 years emoting on the fly.
Unfortunately it doesn't seem to work very well with my G13 joystick to have movement bound to any other keys. It's stupid that say last can't be bound to whatever you want, and even stupider that it is bound by default to the default movement keys...