Any plan to get this fixed in 4.3? dnf is already available in el7.6 and nothing currently prevent it to be installed there.
There are actually two issues, first that dnf Ansible module don't report correct state, when using update_cache:yes. And the second is that it doesn't report packages which will be installed/updated/removed, when using check-model. We need to get this fixed in Ansible DNF module.
Moving to 4.4 due to capacity, but we will try to get that fixed in 4.3.z
I was not able to reproduce this issue with ansible 2.8.1 and Centos 7.6.1810.
Well yeah, now it uses hardcoded yum. So even with dnf installed it will still use yum.
Now is everything working on yum, only reason for any change in ansible role would be if yum would become deprecated.