It’s a common misconception that espresso beans are a different type of bean than regular coffee beans. Espresso can be made with pretty much any type of coffee bean but certain beans have characteristics that lend themselves to making a perfect espresso.
For an espresso coffee, the beans will generally be roasted for longer giving a darker roast. With espresso coffee it’s all about the roast. Lighter roasts tend to result in a coffee which has a more complex character that showcases the origin of the bean although it’ll generally have a more bitter flavour. With darker roasts you tend to lose the complexity and origin character but the roast flavour really starts to shine and with it comes the sweetness of the caramelised sugars. Espresso coffee is famed for its strong, intense flavour and that can only be achieved through using dark roasts.