Self explanatory
Azurill Basculegion Bellossom Blaziken Bonsly Buizel Chatot Deoxys Donphan Duskull Electivire Elekid Giratina Gogoat Greninja Helioptile Ho-Oh Hoothoot Kecleon Latias Latios Ledyba Lotad Lucario Lugia Lycanroc Magearna Manaphy Mantyke Marill Mewtwo Mime Jr. Munchlax Noivern Pelipper Seedot Sharpedo Shaymin Shroomish Slowking Snubbull Sylveon Terapagos Togepi Volbeat Wailmer Weavile Wingull Wynaut Wyrdeer Zigzagoon Zoroark Zorua Zygarde
Pokémon that appeared in the anime before their game debut (Bulbapedia)
theres quite alot but the only few I can remember are chatot,buizel,lucario,zorua,zoroark and ho-oh
On my account, you could play enough of the current version to see a Pokemon before it appears in the show, this accounts for all current Pokemon. The only Pokemon that I could remember seeing before I saw it in the game(s) was Spearow of the very first episode of Pokemon, excluding Pikachu.
