Looking for ideas for Pokemon that trainers would abandon

I'm running a pokerole ttrpg campaign and have a few Pokemon adoption centres around the region, and I don't wanna just fill slots with random Pokemon from a chart or something. I'm looking for ideas for Pokemon a trainer may leave behind.

Some examples i have are an Eevee that doesn't want to evolve, a rusty honedge, Jolteon afraid of thunder, Mimiku that wears a different Pokemon outfit every time you see it, or a Tropius that grows oranges instead of bananas

Be it a physical abnormality, something mental or personality-wise, or it's just how that specific Pokemon species is, any ideas are welcome. Nicknames are optional but greatly appreciated