I am suggesting Threnosia sp. (genus) based on the rather distinctive head thorax and large black eyes (an elongated body shape) which match similar photos of that species in life., see https://bie.ala.org.au/species/urn:lsid:biodiversity.org.au:afd.taxon:c1d82f31-005e-4cf8-9011-ab1d560998e1 Moths of Victoria give a comprehensive guide to Threnosia spp. on their accompanying disc to Part 2. The named species T. myochroa (Heath Footman ) has been originally described as Victorian in distribution, but MoV acknowledges more recent evidence of a wider distribution. Bold Systems 4 shows a distribution of that species cleary including SE NSW and lodged speimensalso from the ACT. T. myochroa males show a faint broad sloping dark band across the mid forewing, although this specimen and the females shown in MoV have plain hindwings - as do other un-named Threnosia spescies illustrated in MoV which look very similar, so would not be easy to distinguish on sight alone.
I am maintaining my suggestion of Threnosia i.e T. myochroa becouase this specimen and that species has a fine white line along the costa of the forewing.
I'm thinking the same thing - many moths have a slightly lighter costa, sometimes by design, and sometimes simply wear, that shows up strongly in a flash photo.