Currently we can import everything from Substance into Maya. But we can not export our Shader base maps from Maya to Substance to work on detail there. (or any other software)
It should be the same kind of Export Dialogue in Maya like Substance has (see attached screenshots), which lets you export all basemaps (diffuse, reflection, refraction, specular, gloss, bump, normal etc. ...) to other applications.
Especially with large node networks, that already obtained tweakings inside Maya, there is no good possibility to get them out at high quality.
The power of Substance is their simplicity: Whatever large shader network was created there, you can export it within seconds whereever you want.
-> This function should support at least 8k and could be merged with Maya "convert to file texture" (Hypershade).
So the great additional advantage would be, to be able reduce large networks (once the artist is finished with tweaking a shader) into overseeable base maps.
That reduces also render time and pipeline workflow and is more artist friendly to read in big scenes.
Export Preset for a selected shader or for all shaders of the scene8k and UDIM support