So, there is no way to automatically do this. However, I can tell you that the Quick Texture macro is fairly simple inside and very amenable to becoming a splatmap instead.
Here’s how I’d do it:
Open up the macro by selecting “enter device”.
The macro functions by combining together Select Wetness and Select Slope and using that to drive a colorizer of your choice. It then mixes in the provided erosion mask atop that.
So, to make the output a splatmap instead, I’d take the mask driving the colorizer and use it to produce 3 bands of material, roughly corresponding to the bottom, middle, and top of the color range. The “Height Splitter” device is perfect for this.
The 4th splatmap channel will then be the same erosion mask used in the device already.
Feed all of those channels to a Texture Weightmap device and, you’re done! Just pipe out the rgba bitmap and put it to a bitmap output device (or use individual weight channels if needed)
Which looks like:
