Female; compare this specimen with an actual R. (C.) formosa female (https://canberra.naturemapr.org/Sightings/3388737)
Notice that the metallic banding on the abdomen is slightly different - the shape of the banding is referred to as 'sublunate' in the specimen above. The face is slightly less yellow/whiter in true formosa, but this changes with the angle. of the light...the shape of the face in profile has some subtle differences too.
The specimen here is another Rutilia (Chrysorutilia) sp. species in the caesia-idesa complex.
Can I confirm that this sighting was indeed made on the 7th of April, 2020 in the late afternoon? This is extremely late in the season for these guys!!!
The photos were taken at 1730, yesterday 7 Apr 2020. It was catching some last rays of sunshine on the side of Mount Ainslie just before sunset. I managed to get 2 close range shots before it flew off.