“…It has attracted many research attentions since most practical tasks need multiple experts' close collaboration [33]. [26], [51], [2], [31], [55], [19], [56], [44], [57], [11], [53], [27], [58], [14], [59] Group [60], [12], [35], [49], [61], [54] [33], [62], [38], [63]…”