"How come in Diamond and Pearl, most of the cross-gen evolutions were not included in the Pokedex?"

The only exceptions were Roserade, Weavile, Mismagius, Honchkrow and some Baby Pokémon I think.Otherwise Pokémon like Electivire, Togekiss, Gallade, Gliscor, Magmortar, etc. were relegated to the Platinum expansion, in fact these mons and their families make up at least half of the Dex expansion.If you wanted to get these Pokémon in DP, you needed to wait for the post-game and get the NatDex, then use the Poke Radar, Swarms, or Dual Slot GBA in the pre-DSi systems.At least this probably won’t be the case with BDSP. via /r/pokemon https://ift.tt/3GYdCpi