This paper deals with cooperative control design for nonlinear multi-agent systems. The control objective is to ensure that a group of agents reaches a formation characterized by external time-varying parameters. First, a translation control design is presented to stabilize the multi-agent system to a circular motion tracking a time-varying center. Then, we propose a new framework based on affine transformations to extend previous results to more complex time-varying formations. Moreover, both control laws are improved adding a cooperative term to distribute the agents uniformly along the formation.