Let's take it one at a time...
Charlotte Ann “Char/Lettie”- it's ok, Char is an interesting nn, one which the more I think on it the more I like it. Not big on Lettie, sounds like an old granny or the girl that isn't the good guys main girl in an old western. And I prefer the spelling Anne
Harlowe Shay “Loey”- I do like Shay, Loey is horrible and Harlow always reminded me of 'harlot'. Also, the cadence is odd. So this one is a big no to me.
Clara Lynette- I'm not sure how to feel on this one, I don't love it, but I don't hate it. Clara is pretty, makes me think of 'The Nutcracker'.
Eleanor Mae “Nora”- Mae seems like an odd choice. This is a very old fashioned name. I detest 'Nora'. 'Ela' would be ok though. I'm still stuck on Mae...
Blythe Eden- Eden is definitely an unusual choice, it's nice. Buy Blythe sounds, skeezy. Like not someone I'd trust. Very off flow in this one.
Katherine Belle “Katie”- Probably my favorite on your list. It has very nice flow. Kate or Katie is cute. Katherine has staying power, almost a regal feel and Belle adds charm.
Violet Luisa “Lettie”- Once again with the Lettie (see Charlotte). I don't know where to start with this name. Luisa looks like a misspelling of Louisa, I'm not a fan of either. Violet is one letter away from violent. Vi isn't a nice nn either. Sounds small town hick trying to be elegant.
So Charlotte(Char) Anne or Katherine(Kate/Katie) Belle