[Inziladun]

Where the Númenóreans were concerned, I would think any "magic" imbued into their weapons was a less potent version of that the Elves were capable of. That would be in keeping with the general properties of the Dúnedain, being basically the most "elvish' among Men, and coming as close to mimicking elvish gifts as Men could.

As for the Dwarves, it seems the instances of their crafting magical artifacts mostly seem to do with stone, the side-door of Erebor which only became accessible at a certain time of the year, and the Doors of Durin at the Moria West-gate specifically. Perhaps that can only be explained by a shrugging note that they do have quite an affinity for stone, and maybe from Aulë their maker they had knowledge of some secret techniques unknown to other races.