The overworld is by and large "rgpmaker default". Chosen for it's very wide support for free assets and tutorials.
Character standing art is largely influenced by free_pancakes, the first artist I had designing characters. Their work set the tone for standing art so I try to keep things in that realm so characters don't look strange during conversations talking to others in like, whole as different resolutions and rending styles lol.
The scene art was always intended to be piecemeal and heavily varied. It's all commissioned work from artists I like, by and large the whole game is a labor of love and the desire to shore up content I was always annoyed other games didn't have or didn't do enough of.