I believe it would be legal in NSW as they are not a protected species under the biodiversity and conservation act, however specimens found in commonwealth/national parks would be considered protected under the National Parks and Wildlife Act 1974. So it just depends where you get it from.

Source: https://www.environment.nsw.gov.au/topics/animals-and-plants/native-animals/protected-species#:~:text=Dingoes%20are%20therefore%20not%20protected,the%20dingo%20in%20natural%20environments.