Self-powered multimodal sensors have been receiving great attention for their potential use in sustainable wearable electronics. In this work, we demonstrate a facile approach for the development of self-powered multimodal pressure-temperature sensors based on an identical ferroelectric copolymer, poly (vinylidenefluoride-co-trifluoroethylene) (P(VDF-TrFE)) for the contact pair materials by switching the triboelectric polarity for the first time. The aligned dipoles in P(VDF-TrFE) critically affect the triboelectric polarity, which relies on the applied bias direction during electrical polarization. This approach enables the identical material-based triboelectric devices with remarkably enhanced output performances even without any additional chemical functionalization or mechanical modification of the contact pair materials. In addition, this work provides a facile approach for triboelectric and pyroelectric hybrid sensors to discriminate multiple stimuli without signal interference.