Balqís بلقيس, the queen of Sheba ملكة سبأ
In modern history, there had been a number of queens in Egypt I think (when it was a kingdom of course), but nowadays there is Queen Rania of Jordan. In Morocco, the wife of king Mohammed VI is actually entitled as princess Salma (سلمى) rather than Queen Salma.
The queen Zenobia (Siptima Zenobia) is controversial, as some suggest that she was an Arab but some say she was purely Aramaic. Her name is sometimes dubbed in Arabic as زينب (zaynab) which is a common Arabic name, and I think in some resources she was given the name الزّبّاء (az-zabbá').
Power-wise, away from titles, there had been a number of women in pre-Islamic era and after Islam who gained power in various ways. Some were princesses by title, and some were even just simple women with no special title, and some might have been even slave girls that raised in power (specially in the history of Andalusia).
OK but first I have to note that contributors here are using the translation for "amazing" wrong. The adjective ممتاز means (excellent) and not (amazing).
The queen is amazing: الملكة مدهشة (al-malikatu mud-hišah).
The queens are amazing: الملكات مدهشات (al-malikát mud-hišát).
Starting a nominal sentence in Arabic with an indefinite noun (as is the case with queens are amazing) is not possible. Thus, the word الملكات (almalikát: the queens) comes defined with AL and it serves the general meaning.