Marxism was designed to be global. Leftists always complained that the existence of capitalism ensured the failure of communism. If not for capitalism, communism would have been utopia for the globe.
So leftist globalists have in mind global utopia in a social and economic sense. Climate change agreements will give the un control over the use of the globe’s resources, including oil, - the central means of production. This is necessary for global communism.
Marx was a huge fan of “Free Trade”.