I'm having the hradest time trading my deoxys to emerald. It knew a move..

Because you obtained it via cheat peripherals, you cannot Trade it or use it in battle. This is a mechanism Nintendo uses to discourage cheating.

You need to have completed the network machine on fire red and beaten the Elite Four on Emerald to Trade Pokemon if you have done both but still can't trade you are SCREWED

Also you can traded either by using the code for Mew in Box1 Slot1 and removing the Aurora Ticket from it and using it at the port in Vermillion city, (But I don't recommened that because if you try to remove it, It won't let you the game will say "Too bad the bag is full" something like that) but it helps for getting an obeying Mew which is the same deal as Deoxys which can't be traded and does not obey. The other way is to use the teleport code to go to Birth Island, and capturing Deoxys at Lv.30. Good Pokemon. Both of 'em. If you use that code, you will then have to solve a puzzle before battling Deoxys. Kind of difficult.