Based on the provided financial data and guidance, Naturgy Energy Group SA exhibits strong credit metrics with a robust rating profile, low refinancing needs, and no current hybrid bonds in its capital structure. The company's leverage is moderate (debt/EBITDA of approximately 3.3x), and its cost of debt is currently low. Issuing hybrid bonds would materially increase the cost of debt without providing significant rating or leverage improvements, as the company already has adequate headroom and funding capacity from operating cash flow.

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