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The energy stored in the batteries of stationary electric vehicles can be exploited to implement smart Vehicle2Grid (V2G) functions by using bidirectional on-board chargers capable of transferring both active and reactive power. To improve compactness, the 3-phase grid can be connected to the primary of a high-frequency (HF) transformer providing galvanic isolation via a direct AC/AC (matrix) converter. This paper focuses on a topology with a 3x3 matrix stage combined with a 3-phase transformer and proposes a control strategy based on a systematic state-selection algorithm together with a simple formulation of the application times. In this way, the transistors are turned on under soft-switching (ZVS) conditions regardless of the phase shift of the current drawn from or injected into the AC grid, enabling high efficiency, compact size, and reduced electromagnetic interference. Performance comparison with respect to conventional topology is also provided.