It is possible to change the color schema of the WMS representation of the soil dataset. The color parameters named "c1", "c2", "c3", "c4", and "c5" have to be added at the end of the "env" parameter in "geoMaps" → "url".
The "env" parameters of "geoMaps" → "url" → "raw_" prefix should look like env=v1:27.39150047302246%3Bv2:34.425498962402344%3Bv3:38.2135009765625%3Bv4:43.2135009765625%3Bv5:55.86349868774414%3Bc1:%23ca0020%3Bc2:%23f4a582%3Bc3:%23f7f7f7%3Bc4:%2392c5de%3Bc5:%230571b0 where %23 is # symbol and %3b is ; symbol. New colors ("c1", "c2", "c3", "c4") are incorporated here %3Bc1:%23ca0020%3Bc2:%23f4a582%3Bc3:%2392c5de%3Bc4:%230571b0