Error when building without compiler

On our artist’s machine we don’t have Visual Studio (or any C++ compiler) installed, as it’s not needed for blueprint-only projects. The artist can make a standalone build just fine, but if we disable(!) any plugin then the build fails with the following error message:

UATHelper: Packaging (Windows): ERROR: [..].uproject does not look like uproject file but no targets have been found!
UATHelper: Packaging (Windows): (see [..]\AppData\Roaming\Unreal Engine\AutomationTool\Logs\E+UE_5.1\Log.txt for full exception trace)
PackagingResults: Error: [..].uproject does not look like uproject file but no targets have been found!
UATHelper: Packaging (Windows): AutomationTool executed for 0h 0m 1s
UATHelper: Packaging (Windows): AutomationTool exiting with ExitCode=1 (Error_Unknown)
UATHelper: Packaging (Windows): BUILD FAILED
PackagingResults: Error: Unknown Error

This is on UE5.1, blueprint-only project. Builds fine with standard plugins. Does not build when disabling any one standard plugin.

My questions are:

  1. Is this normal?
  2. Why would disabling plugins require a C++ compiler to make a build?
  3. Is there a workaround that doesn’t involve installing a C++ compiler?
  4. Same questions for enabling additional plugins that ship with precompiled DLLs.