As Richard mentioned Monzo definitely are planning to expand internationally…the ultimate goal is to get to a billion + users so it’s going to be pretty key! 
Monzo’s eyeing expansion into the US quite closely -
We also know that Monzo’s testing Euro accounts at the moment & judging by the fact that they’re recruiting European language speakers already, that expansion might happen sooner than you think 
Ideally, you’ll also have native-level fluency in a European language so that you can help us serve our users well as we begin to expand across the world.