I tried to compile mingw-qemu-ga-win for CentOS Stream 9/RHEL9.6 
and CentOS Stream 10/RHEL10 and the build failed.
 
CentOS Stream 9
https://kojihub.stream.rdu2.redhat.com/koji/taskinfo?taskID=4608882
build failed during env preparation with error:
DEBUG util.py:461: No matching package to install: 'msitools >= 0.93.93'

This package exists in x86_64 buildroot compose but is absent in s390x.
x86_64-w64-mingw32-widl raise Segmentation fault when compiling qga-vss.idl
 
CentOS Stream 10
https://kojihub.stream.rdu2.redhat.com/koji/taskinfo?taskID=4608888
build failed with an error:
FAILED: qga/messages-win32.rc qga/MSG00409.bin qga/messages-win32.h /usr/bin/i686-w64-mingw32-windmc -h qga -r qga ../qga/messages-win32.mcIn messages-win32.mc at line 1: parser: syntax error. In messages-win32.mc at line 1: fatal: syntax error.
x86_64-w64-mingw32-widl raise Segmentation fault when compiling qga-vss.idl
 
Both builds finished successfully on CentOS Stream Zuul CI during the PRs check
on the x86_64 host. We don't need mingw-* packages for any platform except x86_64.