> At the end of the 99 years Argentina gets control. <
One problem here is that your plan recognizes the Falklands as really belonging to Argentina.
The Falklands situation is quite different from the Hong Kong situation. Hong Kong was always a Chinese city.
“Hong Kong was always a Chinese city.”
Hong Kong didn’t exist.
It was not a city before the Emperor sold it to the UK forever.
Don’t say things you know nothing about.