The PCRaster format doesn't include CRS info. When a raster is converted to the PCRaster map format with the Convert to PCRaster Format tool, GDAL creates an .aux.xml file with the CRS info. Output layers from PCRaster tools should have the same .aux.xml file in order to assign the same projection that is readable by QGIS.
The PCRaster format doesn't include CRS info. When a raster is converted to the PCRaster map format with the Convert to PCRaster Format tool, GDAL creates an .aux.xml file with the CRS info. Output layers from PCRaster tools should have the same .aux.xml file in order to assign the same projection that is readable by QGIS.