Amazing! Congratulations!! 
Pretty sure I might have sent you this already, but interview tips at the end of this guide could be helpful! 
Ahh yes, I think I've read this article a few times. A few questions:
About attire, could I wear my full winter school uniform instead of a business attire? (I noticed how you mentioned that you wore a suit- guys no matter what age look fine wearing suits, but for females, wearing a suit kinda looks like we're playing dress up with our mum's clothing lol.)
As for research, the email sent said there will be industry sponsors- either I have horrible research skills or that the scholarship advertisement didn't say which industry sponsors will be there. What I do know is that the panel will be 3 relevant staff members and a representative from Women in Engineering Program- should I do some research on their background? (My main concern is that I'll look like I just stalked them or something lmao).
Another concern is what if they ask me if I will put UTS down as my first preference? Because tbh, UNSW is my first preference but UTS is a back up. Should I just mention that or will they be salty and make me disadvantaged?
What kind of questions do they usually ask? Do they usually ask generic questions or will they ask specific questions based on the form you sent?
My career adviser told me that the key to these interviews is to be able to answer questions that aren't just 'yes/no' answers but elaborate on them as well. At what point does should I know when I start rambling?
I'm also concerned if they say 'Do you have any questions' because I usually don't have questions until after the event- it takes me a while to let everything sink in. Any tips on this?