SUMMARY
I noticed that the "Send to device" option available in context menu of Dolphin stopped work.
My PC is paired correctly with my smartphone by KDE Connect - in this application my smartphone is visible and I can see media control icon in systray.
Looking at error message, seems kdeconnectplugin_config.qml is broken (not ported correctly).
Please check screenshot with error message.

$ apt list -a kdeconnect
Listing... Done
kdeconnect/jammy,now 23.08.0+p22.04+vunstable+git20231223.0018-0 amd64 [installed]
kdeconnect/jammy 23.08.0+p22.04+vunstable+git20231222.0023-0 amd64
kdeconnect/jammy 21.12.3-0ubuntu1 amd64


STEPS TO REPRODUCE
1. Right click on any file
2. Select and click option "Share -> Send to Device
3. 

OBSERVED RESULT
Error message like in attached screenshot.
BTW. I cannot select and copy error message. Would be nice to this possibility be available. For sure would be helpful in case of reporting the issues.

EXPECTED RESULT
Sending file should work as usual.

SOFTWARE/OS VERSIONS

Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 5.91.90
KDE Frameworks Version: 5.248.0
Qt Version: 6.6.1

ADDITIONAL INFORMATION
Not sure is this meaning.
I wasn't able to update KDE Connect to recent of version in my smartphone (Android 8.0). I reported this here: https://bugs.kde.org/show_bug.cgi?id=478913
BTW. Sending the files in opposite way works well.