If you've logged into myGov to have a look at lodging your tax online and if you've sold any crypto assets then there's a good chance the ATO knows you've done it. My accountant also asked me about it and I hadn't mentioned anything to her previously so when she logged on to the ATO site she must've seen the pre-filled fields as well. So I tried a couple of online crypto portfolio trackers, Cryptocompare which is ok if you just want to collate all your assets in 1 place, but you have to manually input data. It's free at the moment and a bit of a dick to input sell transactions though. Actually a PITA. So I started inputting data into Cointracker which was a simple enough process itself except that it got a couple of things wrong which inflated the value of my portfolio and I couldn't work out how to remedy the problem, so I ditched it and it also costs $299 to generate a tax report. I used Koinly in the end which was pretty simple as well. A bit trickier for a couple of wallets compared to Cointracker but it didn't make any mistakes. It costs $132 to generate a tax report. Coz I don't read the fine print I missed the 15% off code, nice one dickhead you all say. Just putting this info out there for those that may need it.
It's been 15 years since I last filled out a tax form. Not starting now haha. All that goes to my stack instead.