On Still Wakes The Deep, we had to create assets with high resolutions that didn't impact performance. To achieve this, we used a Masking and Tileable texture workflow.
Assets would be textured with an RGB Mask and then each channel would be assigned a texture in engine.
I created an RGB Mask Smart Material in Substance Painter for our artists to get started on their texturing. As a general rule, the use cases were as follows: Red: Edge Wear, Green: Dirt, Blue: Rust.
We created a library of Material Presets to limit the amount of textures and materials in game, which also gave us unified materials throughout. We only need one or two Rust textures for example.
Combined with the RGB Masking, this meant that artists could quickly create RGB Masks for their specific asset, and assign the relevant Material Instances for that asset (Rough Painted Metal, Wood Veneer, Worn Plastic etc).