The AUDUSD has similar with AUDNZD trend. However, it is clear that the AUDUSD moves much more widely than AUDNZD.
If we are not sure the trend, then we can trade AUDNZD
As the published general fundamental information, share prices in American continue to move up without strong volume. Then if the buy/sell balance was broken, and new balance has not been established, the indices will drop quickly.