>>28104221May/Brendan:
Blaziken
Sceptile
Swampert
Wobbuffet
Castform
Kecleon
The rival of Hoenn gets Pokemon to fill in the role of his starter, so there's no reason for them to not get all just to make no starter canon like they did with Red.
Ethan:
Typhlosion (or whatever starter you think he gets)
Togekiss
Sudowoodo
Shuckle
Hitmontop
Gyarados (Shiny)
You can also put Dragonite with extremespeed up there, but its more of Lance's thing, so I didn't count it.
Lucas/Dawn:
Torterra
Infernape
Empoleon
Drifblim
Lucario
Rotom
Like with Hoenn and Kanto, Sinnoh's rival gets Pokemon to fill in the role for his starter, so they can get all.
Wes:
Umbreon
Espeon
Plusle
Skarmory
Metagross
Tyranitar
Plusle is given to you in story, and I picked the non-legendary Pokemon that take the longest to purify.
Hilbert/Hilda:
Samurott (or whatever you think is canon)
Darmanitan
Simipour (same monkey typing as the starter)
Zoroark
Reshiram (or Zekrom)
Victini
Due to Cheren having the monkey that his starter has a disadvantage to during your memory link battle, it leads me to believe he traded his monkey for the protag BW1's monkey.
Victini isn't on that island you get it from during BW1 in BW2.
Nate/Rosa:
Emboar (or whatever you think is canon)
Sawsbuck
Crustle
Blissey
Volcarona
Zekrom (or Reshiram)
BW1 protag can also get a Volcarona, but I didn't want to repeat Pokemon between characters.
Serena/Calem:
Greninja (or whatever you think is canon)
Delphox (would be the starter weak to their main one)
Banette
Tyrantrum
Aurorus
Meowstic (Same gender as who you're battling)
Shauna gives you the baby of her starter, which is always weak to yours.
Threw in the fossils since there really isn't any events that aren't repeats of other games, and both to not make one canon over the other.
The character you don't play as in XY has the Meowstic that's the same gender as them, so in that case why not the protag get the counterpart is my idea on that.