Sign-consensus is one of the newly emerged collective behaviors of multi-agent systems when cooperative and antagonistic interactions coexist among agents. This paper extends the results in a recent work [12] by allowing the graph to be time varying. It shows that the underlying graph only needs to be eventually positive for a suitable fraction of each time interval. In the rest of each time interval, the graph is allowed to have arbitrary topologies. A numerical example is given to illustrate the effectiveness of the control law.