Microgrids are essentially an aggregation concept in low-voltage grids with a high penetration of renewable energy sources. During the last years, we observed a rise in the use of multi-objective metaheuristics in the optimization of microgrids' planning and operation. In this paper, we survey the technical elements of multi-objective metaheuristics, essential for the construction of robust solutions and often ignored by researchers. We identified the main problems of the multi-objective metaheuristics applications in the microgrids' planning and management, and provide explanatory comments and recommendations based on experimental studies and previous works. Additionally, we offer suggestions for comparisons between multi-objective metaheuristics. This work serves as a guide for researchers in the area and will allow obtaining increasingly robust solutions.