It is primarily 2D animation (traditional anime style) rather than full‐3D CGI. However, modern anime often uses 3D elements / CGI assists (for camera moves, background environments, effects, etc.) even when the characters are drawn in 2D. Since this is a major theatrical anime film produced by ufotable (a studio known for high quality visuals) it likely uses a hybrid: 2D character animation + CGI for special sequences/backgrounds. Currently need 1min animation if it is good then need 100min animation.