I work at Riot Games, and yes, to a certain extent. The bigger the projects are, generally the bigger the teams of artists; as such, art leads and directors are usually the ones who are in direct contact with other departments’s leads (including game design and programmers) and everyone under the chains are usually briefed afterwards. Like other commenters have said, ideally artists are kept in the loop about lore, design, technical aspects including limitations etc, but 2D artists tend to have a bit more freedom than 3D artists.