First of all, the concave-convex world and the original god are two different animations, and each animation has its own characteristics and style. Secondly, the secret angel is a new role in the fourth season of the concave-convex world, which debuted in the first episode 13. It is one of the original angels under the creator's code name, Angel T.

So the secret angel of the concave-convex world did not copy the original god.