I think she definitely looks different enough, though if you changed the colour of her clothes it just might make it a little less easy to guess who she was based off of (imo)?
I've run into the same issue where I've made a fan comic/story, but I end up changing many of the characters so much they basically become completely different characters than the original (especially since I tend to write fan characters out of character to fulfill personal preferences). I feel safe to use those characters, even if I admit where they originated from. I just have to be sure they are indeed a different character and not a basic rip-off of the original. So, if you were to break down your character into 10 parts (as in costume, backstory, personality traits, quirks, genre, storyline, etc.), 2-4 parts can be the same as the character you are pulling inspiration from, and the remainder should be something fresh. Or something like that. I'm sure there's not a perfect formula.
In your case, it's even easier since you really just wrote a new character within a fan-story, not just a new version of an existing character (even though she's a clone, she's still her own person). Just try to avoid anything that speaks too closely to Izuna's story (I'm not familiar with it). For example, the creators of Rick and Morty admitted they based their premise off Back to the Future, but for that reason they will never explore time travel with Rick and Morty as they feel that is just too similar to the original.
As you go on with the story, you may find you are making (are have already made) significant changes to her naturally. Characters tend to take on a life of their own, as I'm sure you know. Fully embrace and amplify her differences 
Also, even though you are probably comfortable drawing her a certain way, give her a bunch of different makeovers and switch up her personality in different and unexpected ways. It may seem blasphemous at first and hurt your heart to change your character so much, but just remember it is temporary. You are just playing around, none of the changes have to stick. But the amazing thing is you may find that one of your experiments you may be really into, and you may end up changing your character permanently after all!
