Question: Is it allowed to dye the eyebrows without plucking them, in regards to a woman, so that they [the eyebrows] become apparent with the color of the skin?
Answer: “There is no harm in dyeing the eyebrows. The prohibition is plucking. As for dyeing them with a beautiful dye, then there is no harm. Like with Kohl, when she is applying kohl or when she is wearing what she wears on her lips. There is no harm in that she dyes them with something. As for if she is an old, grey-haired lady and her hair has gone grey, then she does not change it with black. The Messenger of Allah (ﷺ) prohibited changing the grey hair with black. As for her putting something to beautify the eyebrows, and she is a woman with black hair, and she is not changing the grey hair, but she is only choosing some good dyes for her lips or her eyelids or her eyes or her eyebrows, then there is no harm”
The above fatwa of the Shaikh does not mean that it is allowed for the woman to lighten her eyebrows by lightening the hair below and above the eyebrow. The Permanent Committee passed the verdict that it is haram.
See here: https://alifta.com/Search/ResultDetails.aspx?languagename=en&lang=en&view=result&fatwaNum=&FatwaNumID=&ID=9407&searchScope=7&SearchScopeLevels1=&SearchScopeLevels2=&highLight=1&SearchType=exact&SearchMoesar=false&bookID=&LeftVal=0&RightVal=0&simple=&SearchCriteria=allwords&PagePath=&siteSection=1&searchkeyword=101121101098114111119#firstKeyWordFound
Faisal Ibn Abdul Qaadir Ibn Hassan