Violet Rose 
ThDey look a lot more distinct from each other on my main monitor than my second monitor. Color contrast can vary a lot, and different people also internally draw the lines of what point in cyan/aquamarine green actually turns to blue in different places as well.
But really, the way I see it, so what if she *did* look like Lyra? There are a finite number of color combinations to pick from, and show ponies frequently have combinations that are the ideal match for each other. Why should we limit ourselves to only color combinations that haven't been used before, especially when that's often going to amount to aesthetic second-bests? If you had decided (and you clearly didn't, but just making a point) that Lyra's colors were perfect for your character, they spoke to you and you wanted them, I don't see why anything would be wrong with just using them.
Reasonably speaking, somewhere in Equestria there's always going to be multiple ponies with the same color. This is a fan character, you're not trying to sell toys or establish a brand, so it's not like viewer confusion matters either - if people think they look similar, they can think that, but if they try to make an issue of it, just remind them of the facts. And if they still keep on after that, well, they're not being very respectful, so no reason to listen further.
But reall
Reasonably speaking, somewhere in Equestria there's always going to be multiple ponies with the same color. This is a fan character, you're not trying to sell toys or establish a brand, so it's not like viewer confusion matters either - if people think they look similar, they can think that, but if they try to make an issue of it, just remind them of the facts. And if they still keep on after that, well, they're not being very respectful, so no reason to listen further.