My luck with shiny hunting legendaries seems to be going reasonably well so far, finally got shiny Necrozma and completed the Ultra Beyond quest. Don't know how many attempts it took, but it felt like less than 100... It's the third so far, after Fini & Stak (and no non-legendary shinies yet), overall it seems like under odds for all 3 (with shiny charm).
I don't intend to shiny hunt all the legendaries, just the ones that I don't already have from giveaways/RNG abuse in Ultra Sun. Unfortunately, that still seems like a fair number of legendaries... there's still a few I could try to get from US (at very least Lando, Mesprit, Uxie, Ultra beasts), but my 3DS's circle pad broke so I don't think I'll be heading into the ultra wormhole any time soon. :(
EDIT:
Just had a paaaaainful Lugia run. Wartortle in wave 2 froze my Jolteon and it JUST. STAYED. FROZEN. All the while my stupid AI teammates just kept spamming coaching, acupressure, and life dew.

Eventually Hatterene got tired of playing white mage and finally started play roughing, eventually taking out the Wartortle while Jolteon stayed a popsicle. The next battle was Alolan Marowak, who wouldn't do my poor Jolteon the courtesy of blasting it with flare blitz to unthaw it. Hitmontop at least started going for drill run while drapion and Hatterene spammed acupressure and life dew. Jolteon stayed frozen for like another 4 turns before it finally unthawed and got off a max phantasm, which didn't even take Marowak out, it needed another drill run. After that, Lugia went down like a piece of cake.
tldr why is indefinite freeze still a thing GameFreak
