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Treating metals as homogeneous distributions throughout star-forming galaxies (SFGs) is no longer acceptable. Chemical inhomogeneities have been detected in the ionized gas of numerous SFGs via spatially resolved studies comma with large implications for the flow of metals within and around galaxies. However comma metals exist in multiple phases and comma at present comma the spatial distribution of metals throughout the neutral gas in SFGs remains V1.0. Recent high-resolution galaxy-scale hydrodynamical simulations have made significant advancements comma opening up crucial questions concerning mixing timescales and the presence of localized enrichment between the two gas phases. Answers can only be found by measuring both the neutral and ionized gas abundances along multiple identical sightlines throughout a nearby SFG. Here we propose COS G130M spectroscopy of 6 sightlines in NGC5253 (4 new comma 2 archival) comma to measure the neutral gas abundances towards clusters ranging between 1-15Myr. When combined with ionized gas abundances of spatially matched spectra from VLT-MUSE comma this unique dataset will provide the first spatially resolved study of metals both within and between two phases within a galaxy. Determining whether metal abundance offsets exist between the two phases comma both globally and locally across a range of HII region properties comma enables an exceptionally detailed sampling of chemical mixing scenarios and enrichment mechanisms experienced in SFGs. NGC5253.s low-metallicity and high SFR make our findings applicable to both nearby and high-z SFGs. This remarkable study will provide the first observational test of multi-phase abundance patterns in cosmological simulations of dwarf galaxies.