Not that hard, if you know where to search 
This Pokemon has an alternate form
giratina
1 Like
No
necrozma
No. I like necrozma though
spinda
I do not consider that a Form, but just an other pattern.
mewtwo
That is mega evolution, so no as Well.
Hint: this Pokemon needs to have a specific ability for it to change form
greninja
mimikyu
No and no. Getting close
cherrim
No. Hint: psychic
darmanitan
Yes!
alright i can change my forme with an ability too
1 Like
Minior