Yes, there are such printers in existence already --- they either use a laser to melt a layer of metal powder, or spray a binding agent on a layer of plastic powder --- for the latter it's possible to include a colouring agent and get full-colour 3D plastic prints.

Search term is "Laser powder bed fusion" (as opposed to the trademark: "Direct Metal Laser Sintering" as was pointed out below)

https://www.3dsourced.com/guides/direct-metal-laser-sinterin...