Harry is obviously getting a Rowlet no questions asked. Rowlet is so perfect for him because it gets evolved into Decidueye, it has high Special Defense stat.
Anya will have Rockruff because of Pooka and it is very symbolic to her determined nature in spite of everything that has happened to her. It will become into a majestic Midday Lycanroc for sure.
Isa will definitely have either an Oddish with its split final evolutions symbolizing her internal struggle against expectations or Budew because of roses and thorns. Every rose has its own thorn as the band Poison once sang.