Multi-energy generation grids (MEGGs) provide a promising solution for reliable operations of cooperative various distributed energy resources (DERs), supply environmentally friendly energy to remote/off-grid areas, and improve overall system performance in terms of efficiency, reliability, flexibility, and resiliency. However, with the penetration of grids and the presence of various DERs with unpredictable renewables-based power generation and intermittent power loads, the operational coordination and supervision tasks become more complex. The communication-based optimal distributed control approach plays a significant role in MEGGs for coordinating an assembly of spatially and heterogeneous DERs, which improves reliability, efficiency, scalability, robustness, and privacy-preserving compared with traditional centralized-based controls. Therefore, this article aims to study different grid architectures and provide a comprehensive survey of optimal control and communication strategies/systems (CCS) in MEGG. A well-organized and systematic discussion related to the topic has been provided and elaborated on: 1) energy production and distribution with various grid architectures and distributed generating units (DGUs) integration for sustainable power generation, importance of unit sizing and technologies selection, and their implementations and operations; 2) classification on numerous control architectures and techniques, their prominent features and impact on MEGG stability; 3) multiple advanced intelligent control strategies and their essential aspects and merits; 4) different promising communication networks and technologies with optimal communication protocols and standards along with their computational mechanism and potential operational objectives in MEGGs; 5) communication strategies features and reliability issues concerning data volume, data availability, data accuracy, data security and authentication, time synchronization, and the growth of countermeasure...