“Massive Multiple Input Multiple Output (M-MIMO) systems specifically refers to a practical technique for sending and receiving more than one data signal simultaneously over the same radio channel by exploiting multipath propagation”. It depends on several antennas for transferring varied data streams simultaneously. With the increase in count of antennas, the energy or power utilization also gets increased. Thus, it becomes necessary to select optimal transmit antennas that exist as the great challenge in M-MIMO systems. This work introduces a new “Hybrid Sea Lion-Whale Algorithm (HS-WA)” for selecting the optimal transmit antenna by considering the multi-objectives, which increases both capacity and efficiency. The adopted scheme is the combination of both “Whale Optimization Algorithm (WOA) and Sea Lion Optimization Algorithm (SLnO)” that optimizes the antenna’s count and moreover, it finds out “which antenna to be selected”. At last, the supremacy of presented model is confirmed over existing models in terms EE and capacity analysis.