Are the Vanishing Ghosts/Girls/Hex Girls in Every Pokémon Game?

I know that the mysterious Hex Girls have been in X/Y in Lumiose City and On Marvelous Bridge in Gen. 5. I know that there is also a girl that in Sword/Shield that is rather odd with the letter. Are they in every game, and if so, is there ever a reason? Even if they aren’t in every game, is there still a reason why they are in the games at all? Thanks in advance!

Pleaselog inorregisterto add a comment.

No, these ghosts don’t appear in every game, however, there are a lot:

There is also a Hex Manaic in Mt. Pyre that says, “I want to see dreadful things… I can’t leave… Stay… Won’t you stay with me?”

Although it is likely that there are so many of these because they were so popular after their introduction in generation 4, there is a possible explanation for such a large quantity of female ghosts. In Japanese mythology, there are many myths and legends of monsters that appear as female humans, such as the Futakuchi-Onna, a woman with a mouth on the back of her head (the origin of Mawile) and the Yuki-Onna, a 3-metre-tall snow-woman who feasts on the spirits of travelers who become lost in the mountains (the origin of Froslass). These tales are often used to scare children and adults away from doing dangerous things.

Source

Futakuchi-Onna

Yuki-Onna

I hope this helped!