To my knowledge there are only two cases where white settlers were convicted, and subsequently hanged, for their part in killings of Indigenous peoples.
The most widely known case is in relation to the Myall Creek Massacre. In this case, at least 28 unarmed Indigenous Australians were killed on the 10th June, 1838. Of the eleven colonists who took part, seven of them were found guilty and hanged.
The names of those men are:
The four other men involved were to be further examined at trial but the young Indigenous boy who was to give evidence mysteriously disappeared and the four colonists were released.
The other case that I know of involves some escaped convicts who were being returned to Newcastle by the local tribe. One of the convicts attacked the leader of the tribe within sight of the approaching military party and, subsequently, hanged for murder.
There were a couple of other massacres after Myall Creek but none of the settlers involved were ever prosecuted. Probably the last know massacre of Aboriginal people was the Coniston massacre in 1928 and, even so recent, there were no official punishments for the perpetrators.