It took me exactly 1 month. Long story short: our country didn’t get the shiny creation trio event so I began soft resetting for them. I have Dialga, Giratina and I decided to give up with shiny Palkia (the only way I can get it is by Arceus event in Heart Gold which just takes about 5 minutes). I can’t wait to transfer them to XY along with other pokemon from Hoenn (RSE) with updated ribbons.
Here you have video of the process: link. It took me way too long, about 3 hours, I must work to make my paintings even quicker!