This is an irregular verb. It follows the conjugation pattern of the verb passear.
Present:
A Ana trapaceia nos jogos para ganhar.
Ana cheats in games to win.
Preterite:
O Miguel trapaceou durante a prova.
O Miguel trapaceou durante o exame.
Miguel cheated during the exam.
Conditional:
A Clara nunca trapacearia assim.
Clara would never cheat like that.