• Spring would mainly specialise in Grass-type Pokémon with an affinity for Bug and Fairy types so their team would probably consist of Shiinotic, Accelgor, Sceptile and Sawsbuck (Spring Form).
• Summer would mainly go for Fire-type Pokémon so their team could consist of Salazzle, Centiskorch, Pyroar (female) and Sawsbuck (Summer Form).
• Autumn/Fall would specialise in Ghost-type Pokémon so their team could consist of Gengar, Decidueye, Dragapult and Sawsbuck (Autumn Form).
• Winter would obviously specialise in Ice-type Pokémon so their team could consist of Weavile, Glaceon, Alolan Ninetales and Sawsbuck (Winter Form).

You would be correct with spring and summer. Spring is haru (when hanami occurs hence the pink), summer is natsu, autumn/fall is aki and winter is fuyu. The group could be known as the Shinobi no Shiki (Ninja of the Four Seasons).

So, I'm looking for 4 season themed Ninja's to work under Maribella. What would you guys suggest they look like and what sort of Pokemon should they have? I know Winter should have a white haired person and Summer should be like a shimmering blonde. But what about Autumn/Fall and Spring?

Umm, you missed the entire point of getting the flutes, and Cosmo evolving to open the wormhole.

We had the flutes though, Shiranui had one and Chuck retrieved the other from the poachers.

If you don't mind.

So, I've decided to basically make every ice gym leader/elite four member related to Chuck in one way or another.

Lorelei: Aunt
Pryce: Grandfather
Glacia: Aunt
Candice: Childhood Friend
Brycen: Cousin
Wulfric: Uncle
Melony: Aunt

And, due to this, also
Gordie: Cousin