Regarding parental-sibling, aunt and uncle are together, but oi and mei don't seem to be defined. In the case of aunts and uncles, there are no definitions of maternal or paternal, while the next category, Cousin, is subdivided into several categories. If there is no distinction between maternal and paternal for aunts and uncles, I think there will be no distinction for Cousin.
Feedback from Soichi Ogishima: