To quote UNSW: You can apply for transfer into a UNSW degree after completing a minimum of 6 courses (36 UOC). Assessment is based on your ATAR and/or results from university studies. Apply online through UAC (domestic students) or directly with UNSW (international students).
So UNSW will consider your WAM or WAM+ATAR, whichever is better, for your transfer mark.
If you want to transfer after sem 1, then that will be purely ATAR based, but probably more harder to get in unless you have a 96+ ATAR.