Finally did it:. Alola dex completion before bank came out! Almost didn't make it because for some reason, nothing short of a shiny Eevee would get me a Celesteela on the GTS.
I put a buzzwole in and got a celesteela pretty quickly. Even though they are at different points in the mission Buzzwole and Celesteela are more equivalent as there are two of them in each game whereas Kartana and Pheresoma are similar as there are four of each.
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