I do not think there is something like what you mention since a "trading forum" is a somewhat irrational concept, forums as such pay for writing quality content, that does not have a direct relationship with trading since they are very different concepts, You can earn money by trading and working in a forum but separately.
crypto talk is the only forum that paid your for posting , you can earn from bounties on bitcoin talk forum and you can earn from posting articles on steemet , good luck .