If you're honouring an Anzac from Queensland, you may be able to pick up a free-to-use (with attribution) portrait from the State Library of Queensland catalogue - they have over 29,000 portraits online from The Queenslander newspaper. Each one has copyright/reuse info in the catalogue record.
If you're interested in working on women's history and those left behind, The Conversation has this article on Victorian women poets of WWI and at least some of the photographs are out of copyright (you'd need to look them up individually in the catalogues for the institutions that are named as sources to make sure): https://theconversation.com/victorian-women-poets-of-ww1-capturing-the-reverberations-of-loss-108084
A list (with very basic information) of World War I volunteers from the Illawarra region is here. Most don't have Wikitree profiles...
No list, but it couldn't be too difficult to get one .. right?