It is there, but you may have not used the right terms when searching. Here are two relevant pages:
CGT and foreign exchange gains and losses
https://www.ato.gov.au/General/Capi...es/CGT-and-foreign-exchange-gains-and-losses/
Translation (conversion) rules
https://www.ato.gov.au/Business/Foreign-exchange-gains-and-losses/Translation-(conversion)-rules/
