Looking at the tags at Pixiv, it's actually the female hero of Pokemon Conquest. Also, is the Sengoku Mousou tag necessary?
Seems the 戦国無双 is the one that gave the Sengoku Mousou tag. Oichi_(sengoku_musou) was also given from the tags and the association. Other posts from this artis with Oici also have such tags on Pixiv. It looks like the artist only added the tag for the oichi (pokemon conquest)'s character name so, probably doesn't actually have much to do with the copyright.
Seems the 戦国無双 is the one that gave the Sengoku Mousou tag. Oichi_(sengoku_musou) was also given from the tags and the association. Other posts from this artis with Oici also have such tags on Pixiv. It looks like the artist only added the tag for the oichi (pokemon conquest)'s character name so, probably doesn't actually have much to do with the copyright.
At least the game is getting some love, right? That game is criminally underrated.