Supposing you reach Gold with Virgin Australia, you could theoretically do a status match with Delta for Medallion Gold. One thing to keep in mind though is timing since you need to have proof of your Gold status to send to Delta and it generally takes Delta a couple of days to review the request and accept the status match challenge. In any event, per the Delta status match website you'll earn Gold after racking up 12,500 MQMs with Delta and/or partner airlines like China Air (Silver can be had for half the amount i.e. 6,250 MQM). The status would be valid through January 2024.
Since China Air isn't a core Delta partner you won't earn the maximum amount of MQM flying business. In particular per Delta's site on a J,C or D business fare you'll earn 100% distance flown for MQM. The route AKL-TPE-BNE would be a distance of 9,699 which would mean that you would hit Delta Silver Medallion no problem crediting those flights to Delta under a status match. One thing to keep in mind with the status match is you've got 90 days to earn those MQMs meaning if you manage to find another flight with a Delta partner you may be able to hit Gold. In my books, Gold is really the goldilocks status to hold. It gives you priority access to everything, lounge access, better seating on Delta and all partners, etc.
In terms of crediting to Flying Blue, your Auckland to Taipei trip would earn 36 status credits and 30 status credits for Taipei to Brisbane. The lowest status level is Silver and that requires 100 status credits so clearly you wouldn't have enough to earn any status with Air France/KLM's program.
If I were you, I would probably go for the status match with Delta. Keep in mind that timing is crucial here. If you have enough time between earning Gold status with Virgin, and applying for the Gold status match with Delta do that. Otherwise, I'd still try and do the Silver status match with Delta with your current Virgin status. Sure it won't be as fancy as Gold medallion but you'll still get some benefits from it.
-RooFlyer88