In a similar boat to you, NSMB has never worked for me in netplay, even with identical settings, saves, nand, and the same game. Brawl works perfectly with the wiimote, as does Mario Kart, but NSMB desyncs like, 3-5 seconds after the level begins.
Another game that does not work is Tales of Graces, the controller mapping for player 2-4 is messed up, it guards without pressing anything, and most buttons don't do anything, and it has stuff like the HOME button mapped despite never setting it up.
Another game that does not work is Tales of Graces, the controller mapping for player 2-4 is messed up, it guards without pressing anything, and most buttons don't do anything, and it has stuff like the HOME button mapped despite never setting it up.