Online
More information on the specifics. It appears it would just replace the Champions League for the teams involved and there would be 5 spots in the league that are based on some sort of qualification. Sounds kind of like 5 spots will be tied to some sort of relegation system, but it's not clear from this. So, I'm not sure why the domestic leagues should care other than that they have allegiance to money and kick backs from FIFA.
https://www.otbsports.com/soccer/super-league-champions-league-1181522
https://www.otbsports.com/soccer/super-league-champions-league-1181522