Hi, Greenishio. I don't think most manga-ka know about scanlations, but publishers are very upset about them. Most popular manga are immediately scanlated into Chinese, Korean, and English, making it very difficult to sell legitimate editions in countries where those languages are read (which is to say, a very big chunk of the world).
It's a catch-22 situation, because while scanlations have helped to popularize manga around the world, they have also contributed to a Net mentality in which people think they are entitled to get and use anyone's intellectual property for free.
Of course, publishers of translated manga make it harder on themselves by hiring translators who are no more qualified than the people doing scanlations. Again, it's a vicious cycle. In order to compete with scanlations, publishers have to keep prices down, and the only way to do that is to cut corners, resulting in a less-than-satisfactory product.
I have just proposed a shoujo manga line to a certain publisher that will focus on works that will appeal to women between roughly 16 and 35, and Hagio's works would be a centerpiece of that line. As some of the regular visitors here know, I have a good relationship with Hagio, and have been wanting for years to get her works into English--without violating anybody's intellectual rights. I'm not calling "dibs" here. For many years I did nothing about this, partly because I was too busy but also because it seemed hopeless. But now it seems very possible that a publisher will be interested. (I submitted the proposal just about a week ago.)
If you want to do a scanlation, there is probably no one--including Hagio and her publishers--who could stop you. If I find out about any Hagio scanlations, though, as a friend I would be obligated to tell Hagio about it. Knowing her, she would probably not take any action to stop it. But I don't think she would be happy to know that her work is circulating in English, and she had no say over how it was done.
I don't mean to lay a guilt trip on you. As a fellow fan, I understand your feelings very well. In the past, I was tempted to do a text-only translation of
Tooma no shinzou ("The Heart of Thomas") and post it to my website along with instructions on how to buy the original manga paperback. (I never mentioned this idea to Hagio, but I don't think she would have liked the idea of separating the text and images.)
Personally, I hope you will resist that urge to do scanlations for a while. And if my proposal is accepted, and you still want to translate Hagio's work, maybe we can discuss the possibility of you doing it legitimately and for pay.