Is there a Poke Transfer Lab in Diamond and Pearl?

Question

Is there a Poke Transfer Lab in Pokémon Pearl? If so, were?
Also, can I just transfer my Pearl Pokémon to Diamond without having to buy another DS or pay for PokeBank?

Answer 1

There is not a Poke Transfer Lab in Diamond, Pearl, and Platinum, however, there is Pal Park, which is pretty much the same thing, but for transferring Pokemon from Gen 3 to Gen 4, instead of transferring Pokemon from Gen 4 to Gen 5. In Sinnoh, Pal Park is located at the end of Route 221.
Also, you do have to have another system in order to trade Pokemon from one game to another game in the same generation. PokeBank is only for transferring Pokemon to Gen 6 or 7 games, so you can't use that.

Source

Answer 2

The only way to move Pokémon from Pearl to Diamond and vice versa is by trading; the Pal Park, PokeTransfer, and similar facilities are only for moving Pokémon from one generation to another.
A generation is a group of games classified by the total number of Pokémon that exist during the games release, with each generation introducing roughly 100 new Pokémon each. So for example, a Gen 3 game will have just under 400 Pokémon, while a Gen 4 game (like D&P) will have just under 500 Pokémon. Every game since Gen 4 has also included a method for one-way transfers of Pokémon from the previous generation (like Pal Park, PokeTransfer, and PokeBank), a feature that doesn’t apply for games of the same or higher generation.
These games can’t connect to PokeBank directly, so unfortunately, you are going to need two systems in order to move Pokémon. If you have any friends that also play, I would recommend asking to borrow their system if possible (and it doesn’t matter if it’s a regular DS, 3DS or 2DS; if it can play the game, it can communicate and trade with the other game).