1. To be able to comment on transfer speculations that doesn't involve your club, for example when you see City or PSG splashing the cash you should be able to comment "That amount of money spent on him tells us that football is getting ridiculous" or you may try to prevent a transfer to a rival...
It depends on the junior coaching quality of the clubs (not just one club) in the country. To prove it, try setting the junior coaching of all the clubs in a particular country to 20 in the editor, save it, start a new game with that editor and you will find great regens coming in.
As far as I know it depends on the junior coaching rating of the clubs in that country. You can see in the editor that Guatemala has 31 clubs that have their junior coaching rating at 10 or higher (for comparison, England have 31 too), and I had a save where they are runners up in the 2018 world...
Wait... There's something wrong with that challenge. The Hong Kong (China PR) league does not have any qualification spot in the Asian Champions League, so you need to edit the continental rules first to give them a spot.
Can you post the achievements of each player with his club please? Or will it only be posted when they retire? If you score loads of goals without winning any trophies then it's useless....
Not hiding attributes though, giving only an approximation would be better, but if the player is scouted several times by different scouts the range of appoximations will get narrower and narrower until his real attributes finally appear just like usual. Also, for the scout to, at best, project...