Package: qt5-designer

"qt5-designer" package binaries on CentOS:

/usr/bin/designer-qt5 /usr/lib64/qt5/bin/designer /usr/lib64/qt5/bin/designer-qt5 /usr/lib/qt5/bin/designer /usr/lib/qt5/bin/designer-qt5

You may install this package on CentOS with yum install qt5-designer