both are set in the chinese republican era (gorgeous colours and sets :)) and both have amazing chemistry between the leads

both are historical, Royal Feast is set in Ming dynasty which was just before Story of Yanxi Palace which is set in the Qing dynasty. both feature same main leads - Xu Kai and Wu Jinyan

has xu kai and gao yuer, slow burn romance, xukai plays very funny character but smart and caring at the same time much like in AMA