This is what DHA website says about home language tests
Covid-19 and at home language tests
Some testing centres are providing versions of their tests that you can take at home, such as TOEFL iBT – Special Home Edition, OET@Home and IELTS Indicator. We do not currently accept these tests.
Please refer for more detail https://immi.homeaffairs.gov.au/help-support/meeting-our-requirements/english-language/functional-english