For norcal, I am more concerned that, every time a county reaches orange, restaurants open and cases shoot back up.first - I believe youth soccer should be free to play.
Second - ECNL is under US Club Soccer which has stated that all their members must comply with all state and local mandates and restrictions. If Newsom was to ban out of state competition, I imagine that US Club Soccer would take some action.
If they did I have no insight as to what US Cub action might be . Perhaps someone else has a feel for that .
As far as a quarantine goes I think it would be enforced like many unpopular laws ( not conceding that his mandates are laws ) by making an example of a few to put fear into the majority.
Santa Clara just opened restaurants, and the last two days of cases are already awful. Might be just volatility, but we may be headed straight back to red.