If you want to receive credits for taking an OER/ MOOC, you will have to ask permission from the examination board of your study.
At this moment we don’t know how and if the examination boards of the different faculties are able and willing to deal with this. Granting credits for a MOOC that has been taken is complicated. The examination board must be able to establish that the required level of competence of the study is being met, so don’t assume you will be able to get credits. Your main reason for taking a MOOC should be to broaden or deepen your knowledge as an addition to your own study programme.