Mask files can be exported with the Import/Export tool in a similar fashion to texture files. Additionally, WolvenKit will automatically create a custom masklist file, which can be used for importing modified mlmask files.
Masklist files can be opened and modified with any text-editing program.
You can use absolute or relative texture paths.
Importing MLMASK files
Use the import tool to select any masklist file within the raw directory of the Project Explorer. If you don't have one, export an MLMask first.
MultilayerSetup
You can export and import MLSetup files via JSON and edit them with the MLSetupBuilder.