KSA 100 is a different topic to the introduction of different question types. There are different question types that are already in the process of being introduced, the UK CAA was an early adopter and they call the system 'Quadrant', guidance video......
Other Authorities have said they will introduce new question styles 'soon', the time delay apparently dependent on their exam providers upgrading their software. Open questions, as in essay type answers, are not planned but I understand that the LBA have used these for some years. I believe that their use was not compliant with EASA's AMCs which require all questions to be drawn from a common question bank but, well...
KSA100 is an attempt to introduce competency-based assessment, and to some extent training, into ATPL groundschool as a preliminary to introducing competency-based training into ab-initio flight training at some undetermined future date. The net result of its introduction is that candidates will be assessed either continuously or in specific exercises against the ICAO competencies (explanation
here ) during ATPL groundschool. KSA 100 was meant to have been introduced with the new syllabus about now, but the mandatory introduction has been delayed so far by 6 months. The current position is that candidates taking their first exam after the end of 2020 will be trained and examined to the new syllabus and be assessed according to KSA100. Those who take their first exam before that date will stay on the existing system.