So I have a shiny Manaphy I got through Link Trading is Ultra Moon and I was wondering; I know that Manaphy is shiny locked, but is Phione? I tried to hatch a Phione egg and it wasn't a shiny(although, I know it is quite rare for a shiny egg). And so now I want a shiny Phione. Is this even possible? And if so, what can I do to make myself have a better chance at hatching a shiny?
As sumwun stated, Phione isn't one of the Pokémon that are Shiny Locked. So yes, you can breed for a Shiny.