"One or more projects are incompatible with UAP,Version=v10.0" Issue [UWP]

I used your GitHub https://github.com/almorax/dota2-handbook-uwp project to troubleshoot the problem and looks like the problem is with the way the nuget package is referred in "Dota2Handbook" project. In other projects, you have used "PackageReference" way to refer the nuget package however in "Dota2Handbook" project you are using project.json to refer nuget package. When I changed "Dota2Handbook" project to use the "PackageReference" way then I was able to get the latest package.

Note: You will notice that "Dota2Handbook.Infrastructure" project already use the new way to refer Nuget packages

More details on PackageReference : https://docs.microsoft.com/en-us/nuget/consume-packages/package-references-in-project-files

What happened to me is that I have UWP projects that were made in VS 2015 and initially targeting Windows 10 RTM. These projects where updated to VS 2017 and to target Creator's Update. All worked fine, and all projects still used the original project.json style.

Then I tried to create a new Windows Runtime Component project and target Creator's Update initially. Targeting Creator's Update in VS 2017 causes the project to use the new PackageReferences project style. This produced the errors shown in the above question when I referenced the WinRT component from the UWP app.

Rather than converting the all of my legacy UWP project files to use the new format, I target the new UWP or WinRT Component library to Anniversary Edition (which uses the older project.json project style), then retarget to Creator's Update.

Of course, at some point updating the project file may be appropriate, just know that it will no longer be supported by VS 2015. Conversion steps are illustrated here.