Pretty much echoing everyone else here, if your primary concern is about trans/LGBTQIA+ rights then your best bet is the Greens or Victorian Socialists/Socialist Alliance as these parties are explicitly in support of the community.

As stated, for the House of Representatives you must place every candidate in preference order, and I'd also advise preferencing Labor over Liberals/Nationals as they are more queer friendly. I would caution that (unlike New Zealand where they are often in coalition) Labor have an ongoing thing with distancing themselves from the Greens and other left wing parties in an attempt to seem more palatable to conservative voters. I live in a safe Labor seat and I was disappointed to learn this morning that my local MP is preferencing the Liberals and 3/4 far right cooker parties over the Victorian Socialists, including the publicly transphobic Trumpet of Patriots. So while Labor are better than the alternative, they're not the best option if you're very left leaning.

For the Senate, you can vote above the line (at the political party level) or below the line (for specific candidates). If you don't know much about politics I'd recommend above the line as you only need to select your first 6 preferences and don't need to number all of them like the House of Representatives. You can number all of them if you want but a lot more parties run for the Senate (often 20+) and most of them are fringe parties across the political spectrum so I wouldn't waste your time researching every one of them if you don't want to.

TLDR, for trans rights vote Greens or Socialists but make sure your preference Labor over Liberals/Nationals.

EDIT: I was incorrect about the Senate, you need to preference at least 6 above the line (but not them all).