Nah, the amount of English education across Europe is a function of global business and cultural production (Hollywood and the internet). Those will not change even after Brexit.
It has already changed, before Brexit was even a thing.
From 2013
China is now the lead exporter of cultural goods, followed by the United States. In 2013 the total value of China's cultural exports was US$60.1 billion; more than double that of the United States at US$27.9 billion.