While Natal would make a good plantation colony the cape, with its Mediterranean climate, fertile land and its large fish ressources seems much less ideal for plantation, even if they don’t care about settling it it’s likely some azoreans settlers would still go there in the 16th century, and from natural growth alone would number at the very least in the hundred of thousands if not million today.
Portuguese plantation colonies were settled, Sao Tomé has a 10% mixed race population for a reason, if Natal is a plantation colony one could still expect a pre-modern mixed race population size of a few dozen thousand like in Mozambique, it would still end up with some dozen thousands of Afro european today. That would be on top of the cape. Cape Verde also had a significant european migration there and is majority mixed race today because of it
@EnvarKadri
The Dutch were some of the worst settlers in colonial age, mostly because the Netherlands was actually wealthy and a good place to live in and there were less uneducated poor farmers than in any other country, despite the fact they held it for a century and a half they only sent like 2,000 settlers, anyone else colonising , French included, would likely result in a larger population in the cape. Iirc at some point the Huguenots at the cape outnumbered the Dutch.
An ottoman Suez/Pharaoh Canal would likely still be a massive problem from Christian european countries and I guess they would still want to control the second way to the Indies, even if a Christian country controls it rivals would still want to control the way through the cape.
The fertile climate and the vulnerable Khoisan population of the cape make this challenge decently hard, earlier Bantu migration there seems the best shot, the Xhosa were at port elisabeth in the 17th century, if you can both make them go to the cape and also have them become unified (maybe a peripherical client kingdom of a stronger Mutapa kingdom?), if you can have this as well as few european interest (maybe the Dutch keep Angola and the Portuguese decide to focus on Mozambique/Natal to keep control of the Indies, or there is a Portugal screw) along with the Xhosa successfully defeating some expeditionary mission that could keep the cape European free until at least the 19th century, just keep it out of English hands, also preventing a scramble for Africa would help massively, if it can become a decently wealthy agriculture exporting kingdom under european vassalage/influence in the late 19th century it could prevent European settlemnet effort there