Which Nintendo 64 game was the first Pokémon console game with 3D battles?

Pokémon Stadium was the first Pokémon console game with 3D battles.

Pokémon Stadium was released for the Nintendo 64 in Japan in 1998 and later internationally. It presented Pokémon battles with fully 3D arenas, animated models, camera movement, and announcer commentary, creating a major visual contrast with the sprite-based Game Boy games.

The Japanese version originally focused on battles involving a selected group of first-generation Pokémon. International versions expanded the playable roster and included compatibility with Pokémon Red, Blue, and Yellow through the Transfer Pak.

Pokémon Snap is another Nintendo 64 Pokémon game, but it is a photography adventure rather than a battle-focused title. Pokémon Colosseum and Pokémon Battle Revolution also feature 3D battles, though both were released later on different Nintendo consoles.