>>14884760Actually it's dependent on your secret id. Since you traded it, it would no longer count as shiny since it's gone from the game that said it was shiny.
I found out the hard way too. Bred forever for shiny munchlax for my buddy who insisted on having it their nature. Sent the egg. Hatched normal. So I said
"Okay, reset and send the egg back"
MFW they went right into the trade with the normal munchlax, having let the game save and not go back to the egg so I could hatch it shiny for them.