The Newtown High School of the Performing Arts student sent social media into overdrive after singing the anthem in Eora language, along with all 23 Wallabies who revealed they rehearsed all week in the lead-up.
They also belted out Advance Australia Fair in English on Saturday night.
Australia captain Michael Hooper, who had to settle for a second straight draw with Argentina, said the Wallabies were proud to become the first sporting team to sing the Indigenous version.
Rugby Australia instigated the move to coincide with the side's wearing of the First Nations jersey.
"We were practising (the Eora version) during the week and our guys were - there was never a question - proud to have the opportunity to do it," Hooper said.
"I think it sounded pretty good, too.
Wearing an Indigenous jersey and singing that in Aboriginal and then English, it was great and it was great to be a part of.
Fox has previously delivered the Indigenous version of the anthem at Randwick's Sydney club rugby matches and is fast becoming a national icon.
Netballer Kim Green claimed the performance was "the BEST Australian sporting moment I have ever seen" while former Wallabies star Matt Giteau - married to AFL star Lance Franklin's sister Bianca - endorsed Rugby Australia's groundbreaking initiative.
"Special moment in Australian sport - well done," Giteau tweeted.
Calls are already growing for the Indigenous version to become permanent, with Rugby Australia understood to be considering the move after Saturday night's rousing success.
Wallabies playmaker James O'Connor said he "one hundred per cent" supported the version being performed more and more at events around the country.
"Aboriginal people are one of the oldest civilisations and it's a part of us," he said.
O'Connor said Wallabies coach Dave Rennie, of Cook Islands heritage, deserved huge credit for instilling a fresh culture within the group since officially taking the reins in June.
"A huge part of what Dave's brought in is we're coming back to our roots. We've been inclusive," O'Connor said.
"We've got so many nationalities in this group.
"We've sung a lot. We've literally brought the group together by singing a Tongan song, a Fijian song, a Samoan song, a Cook Islands song, a Maori song.
"And now we've got the Aboriginal one and we could feel it this week and we all put in a huge effort.
"We didn't know it was coming until Monday.
"We put a lot of time into learning the words and buying in to it because we feel it's a huge part of our history and our culture and we want to represent."