Additive Manufacturing (AM) facilitates the rapid fabrication of parts with unprecedented geometrical freedom and complexity. With regard to metallic materials, Powder Bed Fusion (PBF) and Directed Energy Deposition (DED) are two prominent AM-processes. PBF processes utilize a focused heat source such as a laser or electron beam to achieve a localized melting of a powder bed. As the layerwise deposition of dissimilar materials across the powder bed is associated with large wastage generation, PBF is mostly used for monolithic materials and avenues towards multi-material combinations are subject of ongoing research. However, functionally-graded components may be obtained by tailoring the microstructural evolution through an adaption of process parameters. In contrast, DED processes are characterized by a direct feed of wire- or powder-material to the process zone, where they are melted by the interaction with a heat source. Specifically for powder-based DED, these inherent characteristics enable the in situ fabrication of compositionally-graded material combinations through an adaption of powder mass flow from two or more hoppers, such that pathways towards multi-material additive manufacturing are unlocked. This promotes the resource-efficient use of material that is aligned with its envisaged application and may also be used to overcome metallurgical limitations when joining dissimilar metals. Above all, these characteristics allow for high-throughput alloy development. However, it has to be noted that both, rapid alloy development and compositionally-graded material combinations demand substantial characterization efforts in order to investigate incumbent phase formations and microstructural evolutions, thus limiting the swiftness of the approach. In this work, we study the use of high-brilliance X-ray diffraction (XRD) and nano-indentation to overcome these limitations using the example of a compositionally-graded material combination of AISI 316L stainless steel and a Co-Cr-Mo-alloy. The results reveal that XRD may be used in situ and ex situ to shed light on the phase formations within the gradient regions. Moreover, the use of nano-indentation provides an insight into the mechanical properties of the gradient regions and interfaces with high spatial resolution. The combination of both characterization techniques eventually opens the route towards a robust and time-efficient rapid alloy development using powder-based DED.