[...] however, if the eyebrows have become so dense that it is unseemly for a woman and incites abhorrence in her husband, it is permissible to trim it to a more appropriate and normal size (Ahsan al-Fatawa Vol.8 pg.76; Zakariyya Book Depot).
Taking the hadith and the various statements of the Hanafi jurists into consideration the following could be concluded:
1. It would be permitted for a women to remove a beard or a moustache that appears on her face. Even though it is facial hair, but since it is to stop women from resembling men, it is permitted. This is the opinion of the majority of scholars, in fact they have said it is recommended, not just permitted. The same will be to bleach this hair instead.
2. If the eyebrows are linked in between, it would be permissible to remove the excess hair from in between to separate them [i.e. the hair above the nose]. The reason for this is that linked eyebrows are looked upon as a defect, hence it would be permissible to remove it.
3. A 'few' stray hairs around the eyebrows would be permissible to remove by clipping them off, if it looks defective, or for married women creates abhorrence in their husband. This does not mean it is permitted to remove a whole line or two of fine hair from around the eyebrows [as is the nowadays].
4. Dense bushy eyebrows may be trimmed down to a more normal size. However, one must exercise great caution in this regard, since one does not want it to fall under the warning of the hadith. If one is not sure how to determine the normal size they shouldnot act on the benefit of the doubt, but rather follow the more cautionary approach and trim less. What so called 'regular' [especially non-Muslim] people consider nowadays as the norm i.e. eyebrows that are shaped in particular unnaturals or reduced to thin lines can not be considered as acceptable in Islamic law due to the severity of the hadith.
5. Great caution has to be exercised in this regard, since the hadith is very strict and there are some Hanafi scholars who have taken more strict position. For instance, Mullah Ali al-Qari (R.A) comments [relating from Imam Nawawi] that plucking of the facial hair is haram (unlawful) for a woman with the exception of moustache or beard hairs (Mirqat al-Mafatih 8:218). The concessions mentioned above are for the removal of a defective appearance and not for purely beautification purpose, hence, caution in this matters is the way.