

Trial by Fire. I just looked it up and one of the first handful of screenshots looked almost exactly like this.
I’ve never played it and never would’ve thought of it, so the W goes to you IMO. All I was confident of was that the graphics and UI screamed “early 2000s PC game”.
It’s been a while, but the last time I checked, the Australian censorship board primarily limits works which can be sold in Australia. I believe that it’s explicitly legal for adults to own anything that doesn’t break any other laws (including decency and pornography laws, but those are surprisingly not terrible IMO), provided that they don’t buy it in Australia.
There are also some laws about using the postal service to transmit classified works, but I think they’re less restrictive; for decades there was a thriving mail-order pornography trade based in the ACT (which had more relaxed censorship than the other states).