Repository replaces some system components (more specifically, rpm and gpgme)
Step 0 - Enable ConfigManagement SIG Yum4 Repos
# yum install centos-release-yum4
Step 1 - Install YUM4
# yum --enablerepo=centos-yum4-testing install yum4
Step 2 - Install Plugins
# yum4 --enablerepo=centos-yum4-testing install dnf-plugins-core
Please report any found bugs (for any components coming from ConfigManagementSIG/YUM4 repository) on Red Hat Bugzilla against Fedora/dnf component (make sure to mention versions and that you use package from CentOS).