Do Muslims in all Islamic countries consider the Adhan and Iqama in the ear of a newborn a Sunnah prescribed by the Prophet, peace and blessings be upon him, and is there a difference of opinion among scholars regarding the permissibility of this act?

It is recommended by the Shafi'is and Hanbalis to recite the Adhan in the right ear of the newborn and the Iqamah in the left ear. This is also the view of the Hanafis regarding the Adhan, while Imam Malik disliked it. The practice of people has followed this recommendation, and it is a Sunnah observed in many countries.