I really liked [name]Amelia[/name] until I realized how trendy it is(and my [name]SIL[/name] told me it was a birth defect!)so now I have some negative connatations with it.
Her twin sisters name will be [name]Charlotte[/name] [name]Quinn[/name].Thanks!
[name]Charlotte[/name] & [name]Amelia[/name] sound better together 
I think [name]Isla[/name] is so pretty!
[name]Isla[/name] is such a beautiful choice but I’ve always loved [name]Amelia[/name] and it goes well with [name]Charlotte[/name] without being overtly “matchy”
[name]Amelia[/name]. [name]Isla[/name] seems trendy and unsubstantial next to your other names [name]IMO[/name].
[name]Amelia[/name] and [name]Charlotte[/name] sound wonderful together.
Definitely [name]Amelia[/name]!
[name]Amelia[/name] by far!
[name]Charlotte[/name] & [name]Amelia[/name] sound more like twins.
[name]Steph[/name]
[name]Amelia[/name], I think. But I also love to combine those names to [name]Amelia[/name] [name]Isla[/name], [name]Isla[/name] [name]Amelia[/name]/[name]Amelie[/name].
I love [name]Isla[/name] but not with [name]Charlotte[/name]
I much prefer [name]Isla[/name] personally, but [name]Amelia[/name] is much more classic (and less trendy) than [name]Isla[/name] will be, I think ([name]Isla[/name]'s jumped over 700 spots in the past 3 or so years, I think), and style-wise, [name]Amelia[/name] and [name]Charlotte[/name] are a much better match. Besides, [name]Amelia[/name] is still less popular than [name]Charlotte[/name]…
I do think [name]Charlotte[/name] [name]Quinn[/name] and [name]Isla[/name] _____ would be just perfect, though, I really love it.
I have never liked [name]Amelia[/name], so [name]Isla[/name]. I agree though that [name]Amelia[/name] is a more classic name and goes with [name]Charlotte[/name] well. [name]Isla[/name] is less expected pairing. [name]Just[/name] depends on your style 
I do like [name]Isla[/name], but my only hesitation with it is that people would CONSTANTLY pronounce it wrong. I wouldn’t use it just for that reason. Of your choices, I’d choose [name]Amelia[/name].
I prefer [name]Amelia[/name], I think it’s absolutely beautiful. If you won’t pick [name]Amelia[/name] just because it’s trendy, just remember that [name]Isla[/name] is rising extremely fast in popularity and will soon most likely be trendy as well.