Custom password format for keychain passwords

Has Apple developed a way to set up keychain suggested passwords so they conform to a specific format?

I appreciate the complex passwords keychain comes up with, however, I have websites that specify “no symbols” and another website that limits the characters to less then 15. When these situations come up keychain is useless as is and I have to resort to making my own less secure password.

am I missing something where keychain generated passwords can be set to a user format?