>>58296448More gym leaders should have one pokemon (but probably no more) that doesn't share their type. Paldea was pretty cool, but then tera-ing into the same type is a little lame.
Will seems a bit eccentric, so I think a Porygon2 would fit well as it's also very psychic like (one of the very few non psychic types to learn psybeam).
While Kecleon and Spinda are pretty psychic like, I'd say that Volbeat and Illumise would be good canidates for Tate and Liza due to their duo dynamic and (at least Volbeat) being able to threaten dark types which are a lot more common in these games than before.
Both Luxray and Lucario are good psuedo-psychic type options for Lucian (Luxray's light theme is somewhat adjacent to the type), though Lucario will be used in the very next fight with Cynthia, so maybe Luxray would fit better. This could also be changed to Porygon-Z in Platinum.
Caitlin is a little tricky, as Mienshao is very psychic adjacent, but it's used by fellow E4 member Marshall. Watchog fits pretty well too and theoretically can stop a ghost type sweep with its immunity and crunch, but it's atrocious. I think Darmanitan is the next most fitting option, but whether it should have it's hidden ability is an interesting question as basically 0 npcs have them and the moveset to make both pre and post zen mode work would be a little awkward, but it think it's the best. In the sequel, Ninetales or Clefable would be good pics too.
For Olympia, no gen 6 (non mythical) pokemon really fits a space aesthetic, but Magnezone (UFO) is pretty close.
Ok, he's not a gym leader or E4 member, but Dexio is apparently a "psychic specialist". I think Spinda works for his first match (level 15), but his second one should be an Alolan Exeggutor, as like Pikachu (he has an Alolan Raichu), you can find Execcute in Kalos, but after time in Alola it will evolve into something that fits the region more.
Bede changes his type, Tulip has her Florges, and I don't like Faba or Avery.