The Fedora plugins documentation page is a little outdated. The page shows to use yum, not dnf and the repo doesn't have a package with the name geany-plugins. I suppose the yum command is still mapped to dnf and that would be better for CentOS users or something. I was hoping to install them all with one shot but it looks like I will have to do them individually for now. There seems to be two versions of geany-plugins-lipsum that conflict as well so dnf install geany-plugins-* doesn't work, either. I don't know if this is all intentional but I found it a bit inconvenient. Most people using Geany probably know how to work around this sort of stuff but it is what it is.