First of all it was never ever possible to pokegen on the (3)DS because PokeGen ran on your PC. What IS possible is dumping the game save and transferring that to your PC.
Secondly, if you were implying homebrew with "it is still possible" then might I remind you that you quoted a comment of mine dating back 15th of MAY this year.
And lastly, regardless of it being possible there is still close to no reason. For checking legality one can just use his brain.exe and for distributing events / fully legal mons etc there are great communities on reddit.
Subreddit PokémonTrades is the best out there for fully legal trading - in fact, over there it is a rule violation to trade modified mons.
(And there are many other similar very active subreddits where trading modified mons is allowed