This study compares the structural and functional properties of four animal-based seafood species—salmon, scallop, squid, and snapper—with their plant-based (PB) analogues using differential scanning calorimetry, cooking loss, and texture analysis. Animal-based seafood showed distinct thermal transitions linked to protein denaturation, whereas PB analogues, made from texturised vegetable proteins, konjac, and starches, exhibited melting profiles reflecting their unique composition and pre-cooked processing. Notably, sous-vide cooking retained moisture more effectively in animal seafood than pan-frying, while PB products’ cooking losses varied depending on species and method. Texturally, animal-based squid was firmer while PB analogues generally had lower structural integrity and softer textures. This study uniquely provides a direct comparison across multiple seafood species and commercially available PB seafood analogues, addressing a significant knowledge gap in how current PB products replicate the thermal and textural properties of real seafood. These findings offer critical insights for improving PB seafood formulations to better mimic animal-derived counterparts, benefiting both product development and consumer acceptance.