What do the pious and expert scholars of Islam say: Is it allowed to cut the hair of the deceased after death?
It is not allowed to cut the hair and nails, or to comb the hair after death. It is Makruh Tahrimi (offensive). (Durr al-Mukhtar)
And Allah ﷻ knows best
Imam Ahmad Rida Khan
Translation by Dr Musharraf Hussain Al-Azhari Translator of Majestic Quran, www.majesticquran.co.uk