XbimTeam have changed the approach to the Nuget packages ID. Xbim.PropertySets.4 has been discontinued, but an alternative is available; the alternative package is called "Xbim.PropertySets". To install it, you can proceed as follows: Case 1: If you want to install Xbim.PropertySets support from scratch in your solution. Search and install the "Xbim.PropertySets" package instead. Case 2: If you have already installed this version. Issue the following command in the Package Manager Console window: Uninstall-Package Xbim.PropertySets.4 –Force Afterwards you should still have Xbim.PropertySets package in your solution. You can safely delete this file and the XbimUpdate folder in your solution.
Get Started
$ dotnet add package Xbim.PropertySets.4Readme
No README available.