Implied Alternate Formes:

Cryogonal:

Black When its body temperature goes up, it turns into steam and vanishes. When its temperature lowers, it returns to ice.

Note: This is referring to Acid Armor, but Acid Armor just liquefies Cryogonal, it doesn't turn it into a steam.

Beartic:

White It freezes its breath to create fangs and claws of ice to fight with. Cold northern areas are its habitat.

Furfrou:

X Trimming its fluffy fur not only makes it more elegant but also increases the swiftness of its movements.

Note: This is referring to its trimmed forms, but those do not create excessive swiftness.

Unfezant:

Black Males swing their head plumage to threaten opponents. The females' flying abilities surpass those of the males.

Note: This is referring to their gender difference, but that is purely cosmetic.

Glaceon:

Diamond As a protective technique, it can completely freeze its fur to make its hairs stand like needles.

Magmortar:

Platinum When launching 3,600 degrees F fireballs, its body takes on a whitish hue from the intense heat.

Electivire:

HeartGold As its electric charge amplifies, blue sparks begin to crackle between its horns.

Rotom:

HeartGold Research continues on this Pokémon, which could be the power source of a unique motor.

Mantyke:

Pearl Scientists discovered that the distinctive patterns on its back differ by region.

Shellos:

Diamond Its color and shapes differ from region to region. In the Sinnoh region, two types are confirmed.

Arbok:

Red It is rumored that the ferocious warning markings on its belly differ from area to area.