You can take them to Dr. Footsteps to get them evaluated, or you can check on the friendship app on the poketch.
If you go to the valor lake front, there should be a little house close to the entrance to pastoria city. Make sure the Pokemon you want to check is first in your party, and then talk to the man inside. He will tell what your Pokemon thinks of you.You can also go to the Pokemon fan club in hearthome city, and the lady there will you tell as well.
Chat with our AI personalities
No, as far as I know.
You give on of your Pokemon the soothe bell and it will get happy faster.(It helped me evolve my eevee and togepi.)
you have to move around with the Pokemon that you want to make happy in the first in the party. You can also feed Poffins or berries.
the trainer by that place, you know ? :)
You cannot obtain Unova Pokemon in Platinum. But, if you know how to code, it is possible to add Black and White Pokemon into your PokeDex, as well as X and Y.