Of course it is possible to appoint a simple moderator as well. There would be a desire, as they say. But I think that here we are talking exactly about having a Polish-speaking moderator in the section. Although I personally don't see any problems in terms of language barrier. But, if forum users from the Polish section really want to have a moderator in their section and they are satisfied with a non-Polish-speaking moderator, they can ask to appoint a moderator for their section from the current moderators.