Only you can catch some only in Diamond and some only in pearl
Leafgreen and Firered, Pearl and Diamond
no
some of the Pokemon are different such as diamond has dialga and pearl has palkia some of the Pokemon are different such as diamond has dialga and pearl has palkia
I think you can only pass Pokemon from Emerald to Diamond/Pearl
Staravia will evolve into Staraptor at level 34. This is for Pokemon Diamond, Pearl , or Platinum Versions. The level may be different in other Pokemon versions.
Yes, and No. You Can find the Pokemon Chansey, But there are no Pokemon by the name of Chansy capturable on Pokemon Diamond, Pearl, or Platinum versions.
You are going to have to be very specific. Different countries have different versions of the game and diamond and pearl have different ID codes.
neither of them is better, they are both the same, but in diamond, you catch dialga, and in pearl, you catch palkia, and you can catch different Pokemon in each game for example: you can catch this Pokemon in diamond, but not pearl but: you can catch this different Pokemon in pearl, but not diamond
yes
Diamond, pearl, and other platinum versions
You can't. Sinnoh is only available in Pokemon Diamond, Pearl and Platinum versions which are set in sinnoh.
the old chateu is only in Pokemon diamond pearl and platinum versions