I could see her potentially fitting into a Gundam movie, depending on the role she played, but I cannot see her as "Sailor Moon", as others have pointed out she's too old to be pulling off a high school student right now. What's more she'd better fit Sailor Mars due to her hair color. Not that this would work well either, given that the thing is so rooted in Japanese high school culture (or what could be called RETRO Japanese high school culture now given the passage of time) that they really should use an entirely Japanese cast. Sort of like casting Heimdall as black (not to stir that up) I'm not big on ethnicity swaps, especially when culture is integral to it. Having whites or a mixed-western world cast being Japanese super heroes in a Japanese school (which is needed to explain the trademark uniforms) feels as wrong as a black Nordic god, even if you were to say make it exclusive to one of the supporting characters. I suppose they could try and relocate it, like they wanted to do with "Harry Potter" (they wanted to make Harry Potter a kid in New Jersey, thankfully JK Rowling and her people stopped them), but that's another bad idea and raises the question of "what's the point?" I mean the character is "Sailor Moon" and your not going to sell that without her wearing a bloody sailor suit, which isn't really relevant to US schools.
That said Anime is stylized to the point where half the problem with live action anime adaptions is that they look ridiculous when done properly with real people. Giving an actual Japanese school girl blonde hair and tying it up in surreal braids is something only a very few people can pull off, and for the most part when you see it on film something like that is more akin to "WTF am I looking at" not selling the average Japanese high school student. As a result most anime works best when left as Anime where a whole world that is stylized can carry off the concepts and appearences without worrying about how a lot of these trademark looks would actually appear if someone tried them IRL.
Now, before someone pulls out pictures of cosplay girls from Japan who CAN pull off Sailor Moon and company (I am aware of such things) understand they represent the exceptions, and being Cosplay girls are not going to be the ones cast in a professional level movie or TV series, or at least without an even bigger disaster. After all one needs to ask "can they act, or do choreography?". Furthermore something intended to be seen walking around in a con is a bit different than doing it in a movie. What's more there are far more cosplay disasters of the whole "WTF that looks freaky" when it comes to things like that, than there are people who look good and have their costumes splattered all over the internet. While this makes the occurance of such a movie, at least as far as casting the characters properly, at least theoretically possible, I think the odds of it being done by any studio capable of funding it make the odds very small. Especially seeing as this still looks surreal (I mean it's a costume, not something you'd expect people to walk around wearing) and you need to have the whole movie match it to the point where it somehow both fits, while still seeming like it could happen.
Not to mention the whole talking cats angle, unless they want to spend a fortune on CGI (we're making Aslan with house cats you see...) which seems unlikely for such supporting characters (yet ones that are around quite a bit and central to the concept)... I have nightmares of something like the "Sabrina: The Teenage Witch" type FX for that.
All said I'm not a Sailor Moon fan (though as a renaissance-geek I'm quite familiar with it). I just don't see it unless they are going for "so bad it's good" and if they are doing that they might as well cast Megan Fox as part of the joke.
I'll also say I've always thought it might be kind of amusing if someone did an old "10th Kingdom" or "Hook" inspired mini-series or movie with anime girls in the future when they are either adults or over the hill. You know, what happens to say Sailor Moon when she's say 55, had a few kids and unlike a few people never bounced back physically, but still needs to transform into a skimpy costume to fight ever present evil, which she is getting too tired and out of shape to compete with. Maybe bring "Devil Hunter Yohko" back at the age of her Grandmother to fight demons like in Frank Miller's "Batman Returns" after they started to take over when she was forced into retirement but now has to come out of it despite frequent need of heart medicine (wow, it's someone's grandma with a soul sword). Things like this have been done before, and with decent effect, but I've never seen it really dealt with within the teen girl anime-hero format.
