I know in the early days of Sahaba and Fiqh it was nt compulsory but rather recommended. Now, I saw that there's an established consensus of jurists of Ahle Sunnah wal Jamah that it is compulsory for today.Here is his reference:
Imam Ibn Raslan, Imam Abdul Bar, Imam Ramali, Imam Badruddin Al Aini, Imam Muhammad Ibrahim Al-Wazir etc. have described in their books that The ijma/consensus has been established that the women's faces must be covered and it is obligatory these days.
[Aun al-Mabud 11/162; Risalatun Fil-Hijabi Was-Sufur 19; Fatawa Ulamail >Baladil Haram 1169; Nihayatul Minhaj Ila Sharhil Minhaj: 6/188; Umdadul Kari 20/245; Al Istidkar 8/542; The Muslim Woman 202; Kashful Gumati al Adilat al Hijab Fil Kitab wal Sunnah, 2nd edition, 161]
Now, what is the actual ruling on this in the Sunni madhabs? Can we go against this consensus? Please answer with references from the early days and also from those who established a consensus of essentiality.