Due to its simplicity, flexibility and conformity, electroless plating presents itself as an attractive route towards functional metal nanostructures. Despite the importance for creating multimetallic materials with enhanced properties, the complex interactions between the components in electroless plating baths make alloy formations a challenging objective. In this work, we outline an electroless plating strategy fabricating Pd−Pt alloy nanomaterials, which is based on arbitrarily miscible plating baths for the individual metals. To demonstrate the excellent nanoscale conformity and homogeneity of our plating system, we apply it to ion track‐etched polymer templates with large inner surfaces as ambitious substrates, resulting in the formation of 3D free‐standing PdxPt100‐x‐nanotube‐networks (NTNWs). Based on the electro‐oxidation of methanol as a model reaction, we utilize the compositional freedom provided by our syntheses for optimizing the catalytic performance of our metal NTNWs, which heavily depends on the Pd−Pt ratio. Within our system, the highest surface normalized activity was found for the Pd20Pt80 NTNW, reaching more than a two‐fold increase of the peak current density in comparison to pure Pt. Overall, our reaction system provides a versatile toolkit for fabricating intricate Pd−Pt nanostructures of arbitrary elemental composition, and constitutes a starting point for designing new electroless alloy plating baths.