The problem with Asuka’s hair is it’s not quite orange and it’s not quite brown- it’s some sort of coppery mix so it’s hard to get an exact colour and depending on the lighting it looks totally different.
Her hair is relatively straight, but also very thick, so I would suggest to get a curly wig anyway or get a curly wig and straighten it. Getting a curly/wavy wig will help it move better and look more natural.
This wig is more on the orange side, but it’s not neon. It’s straight but has layers for movement. It’s also a good length because her hair goes about halfway down her back and not down to her butt.
This wig is a good dark orange colour and even in the description is says it’s good for Asuka. It’s relatively straight and thick but has a little bit of wave in it like her hair.
From an arda Standpoint a I think the best colour would either be pumpkin AR011 or if you’re looking for a more brown wig then warm light brown AR015
For contacts I would see the Shinji contact post and go from there. Although her’s are not as grey ish she does have dark blue eyes. I would avoid Aqua for both of them.