I'm sure the pages will be made once the amiibo physically come out. They also did announced everyone but Sora getting their amiibos soon, with the Sephiroth and Kazuya's amiibo being displayed recently.

All three Splatoon 3 amiibo pages have now been added.

@DivineTajic Thanks for telling me I'll just slink back to Splatoon again I got some pages to make :)