In another “Iono Zone” broadcast, Iono, the newly-revealed Gym Leader, has finally revealed her partner Pokémon—a green Electric-type froglike Pokémon called Bellibolt. Additionally, a gameplay trailer showing Iono in battle has been revealed after the broadcast, which has been included above.
Its eyes are not those things on the side of its head, but rather the two little yellow dots above its mouth. Its belly can generate electricity when it stretches out. It can have either Electromorphosis or Static for its Ability, the former being an entirely new Ability which causes its next Electric-type move to increase in power each time it is hit with an attack, presumably similar to the effect of the move Charge.
You can watch the broadcast of the “Iono Zone” revealing Bellibolt down below.