Bushwalk Australia

I have a Garmin Inreach Mini2 and I am trying to get it to display the map coordinated for the Map Grid of Australia that is shown on hiking 25K topo maps, not latitude and longitude. For the Datum I selected GDA94 and also tried WGS84, but when I go to select the format it show nearly every other country but Australia, it even shows New Zealand. I cannot get it to display coordinates other than latitude and longitude. I cannot believe Australia is missing, I feel I have selected something wrong. Anyone else can display the MGA coordinates?

I don't own one of these, but with all my Garmin devices (fenix 3, Oregon 600, Montana 700), to see the lat/lon format you're wanting, use the Position Format of UTM (with the datum WGS84 or whatever suits your situation).

Try Settings, Units and then change Coordinates to UTM/UPS and Datum to WGS84. This is what I use in an InReach Explorer that doesnt have GDA94 or GDA2020. It will be close but not perfect

Actually - slightly different in the Inreach 2

What is available under format and datum?