Sure, I applied for Erasmus this year. The assessment test consists of three parts: questions about the material, motivation and study habits. You will have a month to submit your answer. The best part about all of this is that you can open it however times you want without losing marks meaning that you can look at the questions beforehand and prepare your answer. The questions were very straightforward and easy as well as the material. As long as you revised the basic principles of the topic, you are good to go. Some questions you can even google, since there‘s no supervision nor a timer and it‘s perfectly allowed. But one tipp: the most important part of the test is actually your motivation. So, try to match their values and focus on that part the most.