Hyperspace Oddity
This team uses the offensive core of Hoopa-Unbound and Charizard-Mega-Y. I was told to delete this team, but here I am.
Hoopa-Unbound The star of the show, Hoopa-U can demolish Stall cores such as Mega Sableye + Chansey, while also threatening Waters that don’t mind Solar Beam from Mega Charizard Y with its STABs and Tyranitar with Drain Punch. It also generally smashes holes in a core.
Mega Charizard Y Mega Charizard Y is a generally destructive wallbreaker, blasting through things that would otherwise check Hoopa such as Landorus-Therian and Steel- and Fairy-types such as Mega Scizor or Clefable. It also soft-checks U-turn spam.
Weavile Darkinium Z is a nuke of a set, taking down threats such as Heatran. Not much more to say here.
Landorus-Therian Landorus-T is the king of OU, and it provides major role compression on this team in terms of a Rocker and a pivot.
Kartana Kartana is the true Water killer. It provides Speed control and slices Waters to pieces, while having Weavile and Mega Zard take care of Grasses. It also threatens Mega Lopunny.
Zapdos Zapdos also brings role compression as a Mega Lopunny check that denies it U-turn while Defogging Rocks away. It also can keep itself healthy without being too much of a momentum sink with Roost.
Maybe sample? I’ve playtested it and it seems to work.