No. One uses Linux plus mingw to cross build for a Windows host.

    ./configue --build=x86_64-pc-linux-gnu --host=x86_64-pc-mingw64

It usually magically just works, as long as the project author has a clue about portability. That's generally the limiting factor.

This. I have a project that has the additional problem that during building some generated Windows binaries have to be called.

On Debian with wine-binfmt the build can call the crosscompiled intermediate binaries and have them executed with Wine. Pretty crazy but it works.

No, you'd use cmake