I'm sure that there is a dnf argument that would provide that information, assuming MythTV is in the Fedora repos, but I don't know what it is. I would also expect that, if you asked dnf to install mythtv, it would provide a list of all the packages to be installed for approval, just as yum does.
I went to Slackbuilds.org to see what it said because Linux is Linux.
It lists 12 discrete dependencies for MythTV, including
Code:
MySQL-python, lame, libass, x264, xvidcore, urlgrabber, perl-Net-UPnP, lxml, faac, perl-IO-Socket-INET6, perl-http-message, libwww-perl
Hope this helps a bit.