Irony is out of all the champions alder was the only to show his personality which atleast proves he is human as well, all other champions had robotic personality and acted like they are a robot.
Assuming you mean the games, every other champion except maybe Diantha had enough stuff going for them.
Lance was the former/reinstated Champion with a whole Dragon-type lineage with a cousin who totally fails to see why Lance is seen as the strongest trainer. By the way,
the man thinks it's okay to Hyper Beam TRAINERS which only points out that he's
harsh despite being nice.
Steven is an avid rare rock fanatic whose good looks charm a lot of women of all ages, and his fascination for stones turns out to be a
very quirky side of him (that people can see in Masters).
Cynthia is pretty much seen as a top Champion who involves herself with old historic findings, is pretty much a sage, and her passion for research has led to many messy rooms with scrambled documents she can't bother to clean.
Alder wanders around Unova while gripping for losing his first Larvesta. He perhaps is the smartest Champion because only certain people become one through their convictions, which is something Cheren learns from.
Diantha is an actress and surprise she is the Champion. Unfortunately, she barely exists in the games. However, the closest we get from her in terms of development is that she doesn't care about passing out on eternal life because she sees getting older as an opportunity to do other movie roles she can't do while young (then again, she isn't seen much).
Alola lacks a Champion (though, unless we take Elio's and Selene's representations in Masters, they both are very fun-loving trainers who are very slow in understanding puns (game literally had those perpetual smiles of theirs as THIS) and wish to expand on learning regional greetings).
Leon is actually meant to represent older players who have grown with the games (they're crazy if they think he's like me, though), which is why he is seen doing a lot of heroics to keep the younger generation in their tracks. But besides this, we all know he royally sucks at directions and is always going out of his way to make Galarian trainers the strongest trainers in the world (none of these two traits show up in the anime, other than the second opening making his bad sense of direction an informed attribute).
