Macross is a series of science fiction mecha anime. The franchise features a fictional history of Earth/Humanity after the year 1999. Within the series, the term Macross is used to denote the main capital ship.
Overtechnology refers to the scientific advances discovered in an alien starship (Alien Star Ship - One later renamed Super Dimension Fortress - One Macross) that crashed on South Ataria island. Humans were able to reverse engineer the technology to create the mecha (variable fighters and destroids), faster-than-light space fold drive for starships and other advanced technologies that the series features.
Below are the characters found available on the site that cosplayers have depicted.