Not that I've heard, no.

I could trade with myself using BasicBoy. You needed to have two open at once but that's not a problem.

I prefer using VBA since it can play Gen. III and it can play Gen. I without fucking up (some sprites didn't show up or show up properly).

TCB-Dual I think it's called can be used for trading with gen I & II games, battling seems to lag in such a way that seems like even my fairly good computer can't transfer the data between emulator windows quick enough.
VBA Link can apparently be used to trade with gen III games, though I'm yet to be able to get it to work.

I recently bought a DS Lite along with HeartGold, r4 ultra and EZFlash 3in1.
I had been playing Diamond on No$GBA and there were a couple of pokemon I wanted to tranfer to HG to carry on using in said game, so I put the Diamond Rom on the R4 card along with the converted save file so it could run on the DS properly from where I left off on the emulator, then borrowing a friends DS I started Diamond on his and HG on mine, then simply traded like normal.

On this same line of thinking, has anyone found a way to use palpark on emulators ?

Google VBALink. It's horribly useful