With Visual Studio Version 15.9.4 a cross-platform Xamarin-forms UWP app was created (.NET Standard project). Then with NuGet sqlite-net-pcl was added. Nothing more was done.
A package for side-loading was created.
There was a warning in the error list: GENERATEPROJECTPRIFILE 0xdef00535 - File or folder ignored due to file attributes (hidden): obj\x86\Release\PackageLayout\e_sqlite3.dll.
WACK failed with failed launch tests and failed supported API tests: sqlite3_aggregate_context in e_sqlite3.dll is not supported for this application type (and 9 more sqlite problems).
A complete programm with a.o. sqlite was successfull packaged beginning of December. After that I did a Windows 10 system restore and installed a new Visual Studio version. Since then no successfull package was produced.