yes
give your Pokemon poffinz
in contests (diamond) or tents (ruby)
no
HeartHome City
sorry don't know
NONE
go to ur house in twinleaf town
Trade Pokemon at the WFC building in jubilife. Win all the Pokemon contests.
Impossible
you have to find out.
you have to be good at contests and have good accessories. there is really no answer to that, just luck.