One week before the exam, buy a one-month subscription to a paid bank (like Aviation Exam or ATPL Guru). Yes, this contradicts "free," but hear me out: Spend €50 for one month. Use the paid bank only for the exact subjects you are sitting for. Use the free banks for everything else.
The ATPL exams are not just about understanding a concept; they are about applying that concept under time pressure in a specific format. atpl free question bank