Felgo actually already comes as a static library, so you would only need to compile Qt statically on your own or ask for a static build if you’re a Qt license holder. There a a couple of instructions and how-tos how to build Qt statically on official documentation and wiki pages, e.g. here: https://wiki.qt.io/Building_a_static_Qt_for_Windows_using_MinGW
May I ask why you want to link statically? Protecting QML files is actually described in our publishing guide here, this is completely independent from using a static or dynamic build.