During this week’s episode of Japanese variety show, Pokénchi, game director Junichi Masuda appeared and showcased new content about Let’s Go. This content started off by showcasing a Pikachu using Surf in battle against a Geodude. In the actual segment featuring Junichi Masuda, they went into detail showcasing various changes with HMs where you call upon Pikachu/Eevee to summon a special move to cut trees or Surf. These moves do not take up your moveslots. It also showcased Eevee using a special Fire-type move called Flare Burn (めらめらバーン) in Japanese.
Source: Serebii
The move Pikachu used on the Surfboard is not Surf but rather another brand new move.
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