As far as I know you cannot trade Pokemon on PC emulators.
The best way to get around this for future playthroughs is to download the Universal Pokemon Randomizer application. This application lets you change the game in dozens of ways including my favorite one which is called "Change Impossible Evos" as seen below
This option makes it so pokemon that need special evoloutions will not need to be traded to evolve. Instead evolving at a high level. For example Haunter will evolve at level 37+ to Gengar.
You can find the application site and download HERE.
If you want to read more on what the change does in emulators you can visit THIS link
Lastly here is a step by step guide to setting up the Randomizer as it is can be a pain to get started.
If you've already started playing, make sure you get your save file out and back it up. If you haven't started a game yet, just download the ROM you're going to
use.
Open your Pokemon ROM in the application. Select the option called "Change Impossible Evolutions." DON'T SELECT ANY OTHER OPTION unless you want to make other tweaks to your game.
Click the "Randomize (Save)" button on the right. Again, this won't randomize your ROM unless you selected other options beyond "Change Impossible Evos"—it's just saving the changes you made.
Load the new ROM file into your emulator. If you have a save file from before, make sure it gets into the new ROM's folder in the appropriate place.
Start the game and play as normal.
Hope this helps.