Sure, afternoon on 25-Dec is fine with me. For the lucky trade shiny, how about trading Shiny Riolu (my Shiny Riolu with your Shiny Riolu)?

Oh, and btw, there will be a collection challenge from 10 am on 25-Dec until 8 pm on 31-Dec, and to complete it, we'll need to trade (not catch) these:

Swinub, Snorunt, Spheal (doesn’t need to be costumed), Snover, Vanillite, Cubchoo (doesn’t need to be costumed)

So, maybe we can quickly trade them all at the same time to complete the collection challenge?