McCarthy grew up in Brisbane where she initially pursued a career in cricket and represented Queensland in the process. She later switched to play Australian rules football for Yeronga South Brisbane in the QWAFL before signing for the Brisbane Lions. She has represented Australia for touch rugby league to at least as high as the under-20s age group.[6] As of 2017, she works as a mathematics and physical education teacher at Clairvaux MacKillop College.[7] She has required an implanted pacemaker since the age of ten.[8][9]
At the end of the season, McCarthy was listed in the 2017 All-Australian team.[14]
Brisbane signed McCarthy for the 2018 season during the trade period in May 2017.[15]
In April 2019, McCarthy joined expansion club St Kilda, along with fellow Brisbane player Nat Exon.[16]
In May 2022, McCarthy was delisted by St Kilda to allow her to explore her options.[17] Following her delisting, she was signed by expansion club Hawthorn as a delisted free agent.[18] At the conclusion of the season, on January 12th 2023 McCarthy retired from the sport after 7 seasons at the highest level.