Virtual quantum maps simulate nonphysical transformations using physical operations and classical postprocessing, but known constructions of virtual broadcasting are operationally inefficient. Motivated by the expectation that relaxing symmetry requirements may improve operational performance, we study virtual quantum broadcasting for qubits under phase covariance. We show that phase covariance, flip covariance, permutation invariance, and classical consistency already fix the structure of the virtual map and imply broadcasting on equatorial states, without assuming broadcasting explicitly. Within this class, we identify a unique map of minimal simulation cost. Remarkably, and in direct analogy with the fully unitarily covariant case, the positive part of this optimal map coincides with the optimal symmetric phase-covariant cloning channel, showing that optimal cloning again emerges as the physically realizable map closest to virtual broadcasting, despite the reduced symmetry. Although phase covariance lowers both the simulation cost and this distance compared with the unitarily covariant case, the resulting virtual map remains sample inefficient.

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• Quantum channels
• Quantum information processing
• Quantum information theory