I also live in NSW, and might be able to help. As the weather in most of NSW is very cold right now due to an unexpected cold snap, the bees have probably suffered some stress in their install if you were anywhere near this cold/storm cell. Otherwise it might just be from the move. Fortunately bees are very smart and just go about their housekeeping without telling us anything. The brood can become chilled easily during times like this and some are likely to die. The bees normally remove them and put them outside. That doesn’t look like an abnormal amount to be honest so I am thinking they are ok.
Mine weren’t very active either until it warmed up a little bit today once the winds and rain stopped, and then they were happy and very active.
I hope this is helpful. I’d suggest to keep monitoring them, and also speak with the keeper you bought the nuc from.