It seems that package does NOT support UTF8

[Mark-Joy]

In windows 10 command prompt, using printf from mingw-io/coreutils:

printf 'αβψδεφγ'
'a▀?def?'

MSYS2 package supports UTF8. using printf from MSYS2:

printf.exe 'αβψδεφγ'
αβψδεφγ

To enable UTF8 support:

• Compile .rc into .res

windres --input utf8.rc --output utf8.res --output-format=coff

• Include .res in linking process. Example:

g++ utf8.res printf.o -o printf.exe

utf8.zip

[mingw-io]

coreutils 9.7 ready for download.
Cheers.