Mixer is a PBR creation suite that uses brushes and non-destructive layering to generate all types of maps.
It's free, but unless you have your own library of maps, alphas, and brushes, you'll need a subscription to Quixel's Megascans archive.
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Its freaking free.
Con Seems to still be in beta
Many features missing, like layer deletion.
Con Free version is technically non-commercial only
But, uh, "exporting" is as easy as opening up the file locations.