I've noticed how tag ecosystems shift between sites. On Twitter/X and Instagram I always use obvious hashtags like #Lillie, #LilliePokemon, #LillieFanart, and #fanart together with broader tags like #'Pokémon', #PokemonSunMoon, or #LillieSunMoon so people who search the franchise or the game find the piece. I also sprinkle in stylistic tags such as #digitalart, #traditionalart, #sketch, or #watercolor depending on medium.
On Pixiv and DeviantArt I lean into the site conventions: plain tags (no hashtag) like Lillie, リーリエ (the Japanese spelling), and Lillie(Pokemon) or community tags like Cosmog or LillieandCosmog. Booru-style sites prefer precise formatting — for example lillie(pokemon) — and that helps collectors find exact character pages. For older threads and Tumblr you’ll see combinations like pokemon-lillie, lillie-pokemon, or pokemonlillie.
I also include content flags when relevant: #R18, #nsfw, or mature content tags, and shipping tags when applicable (Lillie x ?). Those save people time and keep searches accurate. Personally, the small habit of mirroring English and Japanese tags has tripled the reach of my posts, so I always do both — it’s a simple trick that feels worth the extra keystrokes.