I don't think Vanessa would be a good choice at all. Not only is she the wrong nationality to play a New Zealander, but her acting talents are often used to portray either a seductive femme fatale, or an independent female hero who's supremely confident. Neither of those attributes apply to Omega.

Pretty sure @Mitth'raw'nuruodo3 based off the name is speaking from experience. thrawn is a great example of their point.

It's best just to keep her as a kid, making her an adult would be too weird.

Put Temuera Morrison in a blonde wig and call it a day. Would it be convincing? No. Would it be funny? Absolutely.

This is a white woman. We are not doing this again.

^ What do you mean?

Not really sure

I mean I guess it could work or another actor would be a better fit

^^Omega is a clone of Jango, played by Temuera Morrison, who is a New Zealander.

Omega is not white. If she is casted in live action she would need to be of a Pacific Islander ethnicity as Temuera Morrison is.

Very simple: find a Kiwi woman who’s a relative/near relative of Tem Morrison who looks a lot like him who’d be about 40-45 years old. Blondify her hair but keep the rest the same. Have her use the same accent as in the animation, have her work out to be a more muscular yet still feminine.

That is the best case scenario…

….just my thoughts.

Jim