What do humanoid pokemon such as gardevoir and gallade eat? I’d assume humanoid pokemon were omnivorous like us but at the same time the thought of a family of ralts ripping another pokemon to shreds with their teeth (or psychic abilities) is horrifying.

It largely depends on the humanoid pokémon in question. For example, when it comes to the ralts line, you are very astute in assuming they wouldn’t be able to hunt, anonymous. Or, rather, they can’t consume anything with enough of a nervous system to register pain. Therefore, plants and many invertebrates—especially worms, most insects, nematodes, and (for specimens who make their homes close to the sea) sponges and very basic sea life—are fair game to any psychic-type pokémon.

However, with humanoid pokémon of other elements, diets can vary rather wildly. Fighting-types, poison-types, and steel-types are typically carnivorous, for example, as their muscle structure and lifestyles dictate that they need a high intake of proteins found only in meat. Likewise, humanoid grass-types (i.e., cacturne) are typically partly photosynthetic and partly carnivorous. In these cases, their cells possess chlorophyll, but they often live in harsh environments where it’s impossible for them to obtain nutrients from soil alone.

And then you have sableye, which eats rocks.