Sorry, but trade requests shouldn't be asked as questions. The only place to request them on this site is either on somebody's wall or in the chat room. I doubt you'd be very successful with either, though, as chat hasn't been too active recently, and you don't yet have the ability to post on walls, and, even if you did, I doubt posting on people's walls and asking if they have a shiny Zygarde that they'd be willing to give up wouldn't work out too well.
I've heard Reddit's r/pokemontrades is a good place to request for trades, and you'd probably get better luck there, so you might wanna check that out.
https://www.reddit.com/r/pokemontrades/
