Honestly, I planned to breed some of the Pokemon before and send them as baby Lv1s into my Ultra Sun soon. My team would already be predetermined instead of picking from the journey, since I want to do a fresh "unique type challenge", so... I have had bred some of them. Thankfully, most had already been available in Moon, with little bit of exceptions, but anyway....
Obviously, I'll start with them at Lv1, just hatched from the eggs before getting transferred to U-Sun.
I want to try this since I'll love trying as many unique dual-types as possible, making so many colours in my team.
Pokemon Ultra Sun: Twilight Rune
+ Raiya, AloRaichu (Ele/Psy): The cute mascot to foil Lusamine's Clefable. I might want to reapply Electric Shock instead of Thunderbolt in the beginning since having suddenly bolting Pichu would probably be not fun at all, despite TM for it being available postgame last time I played Moon. I just have to remember to keep it a Pikachu until I get that Thunderbolt. And I know life is hell for anyone weak to Dark in Alola but....
+ Neptune, Primarina (Wtr/Fay), starter. The beautiful Water-type to foil Milotic. I hope I don't need to soft-reset for whatnots, but... eh, male is OK. Just undecided on the name, and I hope she won't be way too powerful in story. Name is actually still undecided, not yet figured other better nautical names....
+ Rosalind, Roserade (Grs/Psn), Princess Grass-type to foil Liligant. Comes with Fire Hidden Power, but I'll also limit her moves. Leaf Storm or Giga Drain at start maybe OP too.
+ Yukino, Frosslass (Ice/Gst), mysterious Ghost-type to foil Mismagius. Also with Fire HP for no reason. Limiting with no Ice-move for the start?
+ Lyon, Lycanroc (Roc), event Rockruff. This one's interesting, its design has warmed over me now. Hoping for female one, so I can name her after the knight girl from Suikoden V who will hold the Twilight Rune (hence my run's title).
+ Mimi/Minami?, Loppunny (Nrm), my MegaPokemon of choice, and the strength Normal to foil Bewear. I rarely used Mega-Evolution in story before, so this is good time to try it out, assuming Mega-Evos are accessible midstory (I don't know yet if it is, I just heard rumours that it is, but better not get spoiler now).
All of them will be female. Except Primarina if I'm too lazy to soft reset to get one. I'll prioritise nature more than gender, it's meaningless while I can't have her in Dive Ball.
I may want to bring backup though, such as an Umbreon, or if I have time, a Flygon. Want to try using them too.
And no matter the circumstances, I'll be bringing Moon's Lunala (Nebby herself) in the very last showdown to teach Sakaki and his sorry Mewtwo some good nightmare.