The reason why the Dutch settled the Cape of Good Hope was pure accident. Van Riebeck's ship was wrecked there in 1652, forcing the surviving castaways to spend a year down there and cultivate the land and discover that the soil was fertile and the climate one where crops could be grown. Prior to then European ships of various nations might land there and even use the cape as a sort of post office--but they did not believe one could live there--because the natives did not grow crops but more importantly, there were no trees. Just a fymbos scrub. That's why Bartolemeo Dias did not settle the Cape way back in 1488.
If a BriA lot of different TLs could branch out depending on whose ships get wrecked on the Cape and when. If Bartolemeo DIas's ship gets wrecked in 1488 but his crew survives while he and a few crew members make it up the coast to Sao Tome, discovering diamonds on the Namib Coast along the way, there will be a Portuguese colony at the Cape before Columbus sails in 1492. If a British ship gets shipwrecked the same way, a British colony on the Cape. Ditto a Danish ship. Or a French ship. In any of these cases, Southwestern Australia will look a lot more attractive to the VOC as a way station for Dutch sailors.

Now turn the globe toward you so that the Antarctic faces you and measure out distances. To get to the Cape of Good Hope, sailors must cross the Atlantic, sail along the Brazillian Coast to at least Rio de Janiero before sailing into the open ocean, cross the Horse Latitudes where they may be becalmed and finally catch the Westerlies. If one is lucky, one can make the Cape from Rio in about a month and Western Australia in another month. Which is about when scurvy is about ready to start setting in.

And that is why the Dutch were so eager to take over Brazil in the Mid 17th Century and why the Cape was so useful to the Dutch.
Now change the TL to one in which the British have discovered that the Cape is fertile. The British East India Company has discovered by accident that there is good land at the caCape that it can sell concessions to and make money on. And in doing so, keep ththeir competitor the VOC away. So they sell a concession at Table Bay to one group of PuDissenters, Saldanha Bay to another group, Mossel Bay to a third, Algoa Bay (Port Elizabeth to a fourth and the Great Fish River (East London) to a fifth. And thereby make it so that the Dutch can't use the Cape without paying at least a stiff fee--when England and the Netherlands are friendly). That's a real problem on the return trip, since the Cape of Good Hope is notorious for unfavorable winds for ships trying to round it from the East. It can take a month or so to round Cape of Good Hope, while the crew gets sicker and sicker with scurvy. And they don't know how to preserve citrus fruits yet.
So the Dutch may be intrested in going round the world the other way. To the East Coast of Australia from SW Australia. One month and mind the shipwreck coast east of Adelaide! To New Zealand. Another two weeks to a month. From there to the West Coast of Patagonia or Tierra Del Fuego. Less than two months if you drop down to 55 deggrees and if you don't miss the left turn at Cape Horn and turn into the Flying Dutchman!
Then another few weeks to the Rio Negro, or White Bay (Bahia Blanca, Argentina). So with a series of way stations, the VOC can safely keep crews alive and healthy using the powerful Southern Westerlies for a one way East to West circumnavigation of the world before turning back North home to the Netherlands. Cumbersome, but THE BLOODY BRITISH DON"T GIVE THEM ANOTHER CHOICE!
It's the colony at Bahia Blanca that makes SW Australia work. Because one month across the Atlantic and one month across the Indian nonstop is two months from Bahia Blanca to SW Australia. A week or so in port consuming fruit with vitamins and another month to Batavia or Kupang or Makassar (maybe Makassar is more conveniently located for VOC headquarters reached via the Lombok Strait from "Stirling Bay" this TL. Then back to SW Australia, a stop on New Zealand (probably at Invvecargill, since they can pick up sealskins there) and another 8-10 weeks back to Bahia Blanca. Then home. It works.And it gives the Dutch control of everything south of 30 degrees South except South Africa.
Now