Are the supplications "O Allah, make the exam questions from what I have studied" and "O Allah, show me in a dream a vision from You, not from Satan, in which You teach me the questions that will come in the exam" considered an transgression in supplication or a request for knowledge of the unseen?

We do not see any transgression in this supplication, as it contains no sin or request for the impossible. The ultimate goal of studying is to gain knowledge, so you must be diligent and keen to increase your beneficial knowledge, as Allah the Almighty said to His Prophet: (And say, "My Lord, increase me in knowledge.")