I stumbled upon this (below) and wondered, if there are translations of the Atthakatha before it was translated to Singhalese or of the Sinhalatthakatha before it was retranslated to Pali.
II. The history and development of Pali commentary (Atthakatha)
The commentaries as we know that the result of a long development based on two kinds of older sources. According to chronicle books Mahavamsa and Dipavamsa mentioned that, commentaries are assumed to have been recited already on the occasion of the 1 st , 2 nd and 3 rd Council. After the 3 rd Buddhist Councils, when the king Asoka sent out his son Mahinda. Then Mahinda is thought to have brought them to Ceylon in the third century BC, where they were translated into Sinhalese , to be retranslated into Pali by Boddhaghosa. Consequently the old and superseded Sinhalese commentary is called Sinhalatthakatha.
from: Introduction of Pali commentaries by Amkhar Bounzouay,