My version is iOS 18.6.2 (22G100), watchOS 10.6.1 (21U580), macOS 15.3.1 (24D70), Xcode Version 16.4 (16F6). My iPhone can connect to Xcode and complete app installation testing. I have connected the iPhone to Xcode via USB, and both the iPhone and Apple Watch have been set to trust this device. The iPhone has Developer Mode enabled, but I cannot find Developer Mode in the Privacy & Security settings on the Apple Watch. As shown in the image, the Devices section in Xcode's Developer Documentation displays my iPhone but not the Apple Watch. However, the Open Console for the displayed iPhone shows my Apple Watch—actually two of them, though I only have one Apple Watch (the other might be from a previous backup). The iPhone app installs and tests normally, but the Apple Watch app cannot select a target device and fails to start installation. How can I resolve this issue?
Regarding the issue of Xcode not displaying Apple Watch devices
I cannot find Developer Mode in the Privacy & Security settings on the Apple Watch
It's right at the bottom of Privacy & Security. Are you sure you can't find it? Is it definitely not there?