Taiwan’s laws are not designed for the 21st century, so digital nomadism is illegal unless you have open work rights (there are several threads about this). An ARC won’t fix this.
Your Chinese ancestry may qualify you as an ROC national without household registration, which makes immigration less difficult, but you still have no right to work, at first.
As an Aussie, you can apply for a working holiday visa, which is equivalent to an open work permit, with an expiry date.