Duke
The code NXXT doesnt refer to an overseas x-trade ... it is a type of crossing or "crossed trade" (known as a NATIONAL BEST BID/OFFER or NBBO Crossing), where a trade has resulted from matching a buyer and a seller of a particular stock that are both clients of the same broker.
An NXXT is a crossing that occurs at the current NBBO price and has been reported to the ASX.