I currently use AppShortcutsProvider successfully to register AppShortcut items that appear in the Shortcuts app and in Spotlight on iOS 18 (built with Xcode 16.4). However, I'm unable to set a branded image asset (SVG or PNG) as the tile icon — only SF Symbols are allowed via systemImageName: String, and specifying an asset name results in a blank icon in the UI.
Interestingly, other apps (e.g. Notes, Talabat, Photos) seem to display a custom image as the shortcut’s icon in Shortcuts, despite current documentation stating otherwise. I'm kindly requesting Apple formalize and support this capability.
There is API for this — take a look at this older thread for screenshots and code.
— Ed Ford, DTS Engineer