プラントベース is a marketing word. It usually means the main ingredient is plants, not that nothing animal is inside. Plant-based burgers, nuggets or milks can still contain egg white, milk or honey as a minor ingredient. Same caution for 植物性 (shokubutsusei, plant-derived) and 大豆ミート (soy meat). Check the allergen line for 卵 and 乳成分, then read the whole list. Often a great product, and a good place to start. Just not a promise.