Pretty sure the Tapus share the Oricorio types. Electric/Fairy, Psychic/Fairy, Fire/Fairy and Ghost/Fairy.
Missing models reveal our Totem Pokémon:
[Normal] Gumshoos/Raticate
[Electric] Vikavolt
[Grass] Lurantis
[Fire] Salandit-evo
[Ghost or Fairy] Mimikyu
[Dragon or Fighting] Kommo-o
I can't find any listing with a missing Wishiwashi model, which is weird since it's been pretty much confirmed as a Totem mon (and we do have a Water Captain, so we need a Water-type Totem, I'd assume). I don't know if it might point toward there being more Totem Pokémon (and thus trials), but if we include Wishiwashi, then we have seven... I wouldn't be surprised if one more was missing to complete the Gym-like number eight. Easily divisible by four islands, too. My guess in such a case would be an Ice trial maybe - with either Crabyeti or Sandslash/Ninetales. Could be version-dependent like the first one.