For Kanae, the main thing was a full name that probably existed in Edo Period Japan... and while most people didn't really have surnames back then, you can't really do that in game, so! Tomatsu existed in records from back then but wasn't like. An Extremely notable one like Oda.

W'htal's name was reverse engineered into a miqo'te name from a Japanese name, because he was a Kugane merchant first and I picked his race second! Since miqo'te aren't seen a ton in Hingashi, I decided he'd come from elsewhere but got the name he went by (Wataru) from it being an easier version for the people he worked with to say. Initially he Was going to be a Tia but I realized it wasn't useful for him, so I picked Corax. I knew I wanted to start with a corvid based name because he's a tricky guy (putting it kindly) and crows tend to have trickster associations-- turned out the Japanese name for corvus corax was ワタリガラス-- the watari part can be written with a kanji that can be also read wataru ☺️