This sample demonstrates how to add a Legend component instance to a LayerList component. This is achieved by adding the legend string to the panel of the appropriate ListItem in the LayerList component.
document.querySelector("arcgis-layer-list").listItemCreatedFunction = (event) => { const { item } = event;
// Exclude group layers, otherwise the legend will be displayed twice if (item.layer.type != "group") { item.panel = { content: "legend", open: true, }; } };