I am exploring ArcGIS Online for teaching and would like to include ESRI's Terrain Aspect Map and Slope Map as context layers in a (swipe) web mapping application I am creating. They look great in the map, but the legend for each is irrelevant (see below) so the reader cannot easily interpret the map. Slope is fairly intuitive (for relative rather than absolute values), but aspect, as shown, is less so.
Is there any way that I can include meaningful information in the legend, or on the web map at all? If I look at the layer's Item Details, the page held by ESRI shows a simple legend for each (below). A way to get these in to my web map would be helpful, but the Description panel does not allow images.
Any suggestions, please?