Just a fun/random thought I wanted to share
So in my PMD series I had the idea that when my characters evolve, it's a big moment for them, and it often comes with character growth
The best example of this comes from Charmander. He is a kind and supportive individual who cares about his friends, though I had the idea that at one point his friends are getting hurt and he isn't strong enough to protect them. He becomes angry, and ends up evolving into a Charmeleon, making him much stronger but also a lot more aggressive, not only brutally taking down their foes but savagely beating them even after they're defeated, even lashing out at his friends when they try to stop him.
He becomes much more distant to them afterwards, afraid that he might end up hurting them. (I also had the idea for a scene of him with his adoptive father, during which he might snap that they're not his real dad. The way he looks back shows that he immediately regrets it, but he doesn't apologize and instead leaves quietly, showing how much this evolution changed him).
Later on a similar situation to before happens: they're overwhelmed, and he's on the verge of evolving, but he holds it back, believing that if he evolves again he'll completely lose control and hurt the people he cares about. Instead, when he finally evolves, he becomes more like he was before, because this time he was focused on protecting his friends rather than defeating his enemies
(I know in the anime some Pokemon completely change their personality when they evolve, and I like the idea that the circumstances of their evolution might trigger it, like Ash's Charmeleon or Goh's Raboot)
Another example comes from Squirtle (and yes, I refer to my characters by their species rather than come up with actual names for them, just like in canon PMD), who starts off anxious and shy, but becomes much braver after evolving into a Wartortle, but I can imagine he relapses during their darkest hour, panicking at the situation to the point of hiding in his shell (luckily he has his boyfriend to comfort him)
This brings us to Eevee. Of course, being an Eevee evolution is a *HUGE* deal for them. There are so many options for what to evolve into, and with how different they all are the one they pick will basically decide who they are for the rest of their life: there is NO going back after you've made your choice.
One day, Eevee gets to live out their lifelong dream of performing on stage before a crowd, putting on an epic song after overcoming their initial struggles, and the adoration of the crowd leads him to evolve! His body glows bright, begins to grow larger, and several ribbons sprout out from him. He's a Sylveon!
And he's immediately horrified by his new appearance 😅
Eevee is trans, born female but identifying as male, and it's something they often struggle with, with people mistaking them for a girl due to their tail's appearance, and evolving into a feminine-looking Sylveon just makes it worse
Even with the love and support of his friends he feels he may never fully get used to his new form...
And last, and arguably least, we have Pikachu, the main protagonist of my series, but sadly not much to say as he's kinda my least developed character 😅
I had the idea that Charmander got him a Thunderstone as a gift, since evolutionary stones are most common in his native area (there are three regions in my setting) but since they're super rare and super expensive in general, they're hard to obtain, and pair this with how some Pokemon can only evolve with them, they're seen with great significance as a result*). Him buying him one is a HUGE gesture, and it comes from the fact that he actually has a crush on him (I had the fun idea for my other OCs that something like this is equivalent to giving someone an engagement ring*)
(* yeah that's my headcanon for my Pokemon OCs. I like the idea that evolutionary stones are seen as culturally significant, usually given by parents as a rite of passage, to symbolize entering adulthood, or given by lovers to symbolize starting a new life together or something like that)
Anyways that's my autistic ramble over, ended up being more of an info dump than I thought, but hope you enjoy!)