Currently, on Android, if you share something to KDE Connect, you have to press on the KDE Connect icon through the share dialog and then the KDE Connect app will open for you to select the desired device.
With this option, it would be possible to set a default device which you can select to instantly share something, skipping the part where the KDE Connect app opens for you to select the device.
Moreover, if there is only one device available from the KDE Connect app, then it will be the default device chosen for share.