If a user finding sending smerits to posts in different languages, what does this mean? how to investigate it? and how/where to report it?
I don't think it's wrong sent merit to local board even you are not native with them. For example once I visit local board, my browser automatically translate in English. And if that time I notice any merit worth post then obviously I can send merit. Or who know may be that guy use Google translate.
But yes, you might investigate that they are connected or not somehow. Just sent merit each other doesn't prove they are connected. If you have solid evidence about connected account then you could open thread about it. Otherwise just sent merit on different languages will not consider merit abuse in my opinions.