Pokémon: Cryogonal
Type of the Gigantamax Form: Ice
G-Max Move Name: G-Max Sudden Light
G-Max Move Type: Ice
G-Max Move Description: If the target have positive stat changes, remove them and the target becomes inflicted with a whole new status effect, called Agitation.
Agitation: Non-volatile status, thus does not wears off if switching away. The victim's Special moves deals half damage, and their Ability, excluding RKS System and Multitype, become deactivated. If Agitated, the victim cannot be inflicted by Burn, Sleep, Poison + Toxic, Paralysis or Freeze, while it cannot be Agitated if it is already inflicted by any of those statuses. Agitation can be healed by a Lum Berry, Heal Bell, Aromatherapy and other methods that remove non-volatile statuses.
Competitive Overview: We never have any new negative non-volatile status since the very first Generation, so why not making a new one? Keep in mind that, while Cryogonal is pretty fast and can take advantage of its Special bulk even further if things goes right, also have to deal with limited movepool.
Fun Fact: "Sudden Light" comes from Cryogonal being able to learn multiple light-based moves not only Flash Cannon through TM/TR, but also Solar Beam, Reflect, Light Screen, and Aurora Beam naturally, so I decided to base it on this oddity.
Pokémon: Sirfetch'd
Type of the Gigantamax Form: Fighting / Flying
G-Max Move Name: G-Max Bravery
G-Max Move Type: Fighting
G-Max Move Description: Hardcoded to 140 BP. Raise user's and ally's Attack by 1 stage.
Flavor Description: A Fighting-type attack that Gigantamax Sirfetch'd use. Although it raise Attack like Max Knuckle, this G-Max Fighting move is significantly stronger.
Competitive Overview: Not the most exciting effect, but being hardcoded to 140 BP that Max Knuckle and Fighting-type G-Max cannot reach is what gives it a massive edge over other Max Fighting moves. Helps that Sirfetch'd base Attack is already grand. Flying is for Max Airstream STAB.