Yes, we know about Sunman. In addition to the suspiciously similar “original” character, there may be more evidence Sunsoft was developing an unreleased Superman game for the NES.

Legend has it Sunsoft was developing a Superman game. The Lost Levels has an article about Sunman, another unreleased NES game that looks like a Superman game. Now a build of the Superman game is out, also graciously provided by the Lost Levels team.