Hosting sites compatible with Draft Dominator and MyFBG are Yahoo! Fantasy, NFL Fantasy, CBS Sports, MyFantasyLeague, FFPC, RT Sports, Sleeper, Fantrax and Fleaflicker. As of May 29, 2019 this is the complete list of supported fantasy football league hosting sites. Please note that not all of these providers may have actually opened for the 2019-2020 season - if you are having an issue linking to a 2019-2020 version of an established league, please check that the league hosting service is actually up and running for this season.
A note from Joe on ESPN Fantasy League Hosting:
"ESPN fantasy football for 2019 is currently in BETA and we are awaiting a stable version.
We love ESPN and of course Footballguys will include ESPN.com league hosting in our Draft Dominator and MyFBG software once ESPN has released their stabilized version of league hosting.
We're just not able to build our product to BETA versions of software or operating systems. We'll be ready when ESPN gets their stable version ready. Let's have a great season.