Both have a main character that don't know anything about playing their respective show's game and are later taught them, but are also similar because they both practice martial arts, both show's have colorful cast of characters, and both show's depict characters fighting in a tournament to hone their skills in a game, Buddyfight is a card game battle and Gundam Build Fighters Try is a gunpla battle. Both main characters relate their martial art use in their battles.
Both series were made with quality 2D animation, from the realist moments to the Super Robot Zero-Time moments.
Gundam Build Fighters Try features miniture model kits made to move like actual mecha (mobile suits) with the invention of Plavsky particles
Star Driver: Kagayaki no Takuto, features giant statues called Cybodies that can be used as mecha in a dimension called "zero time".
The trio of Fumina, Yuuma and Sekai resemble Sugata, Wako and Takuto, respectively.
Taking place several years later. Both anime has new characters in the same universe who enter the world of GunPla( Gundam Build Fighters) and CardFight Vanguard. The original characters from previous season will make an appearance to help the new main characters out. One series is a mecha and the other a card game. Both anime airing this Fall 2014.