VS will always apply a `.globalconfig`, not just when analyzers are activated like the CLI build does. Use a different name and explicit inclusion to get consistent behavior.
You can minimize the effort of creating new test projects according to your project's conventions by defining some global default MSBuild properties. A new test project csproj will then be a five-liner consisting only of the SDK and TFM.
If 3rd party assemblies unnecessarily target an inconvenient bitness, either convince the 3rd party of AnyCpu or force AnyCpu on the assembly yourself (with permission from legal).
Speed up development of dependent nuget package chains by creating sibling projects that use ProjectReference instead of PackageReference for instantaneous feedback.
When developing plugins for an application that is shipped as both 32 and 64 bit, it may be possible to publish a single artifact working with both by building as AnyCpu, ignoring the MSB3270 warning.