Perimenopause combines ovarian hormone variability with changes in stress regulation, inflammatory-redox balance, neuroplasticity, and gut-brain metabolism, creating a period of increased vulnerability to depressive symptoms, anxiety, irritability, and sleep disturbance. This narrative review synthesizes evidence on plant-derived foods, bioactives, dietary supplements, and standardized botanical preparations relevant to emotional health during the menopausal transition. Targeted searches of PubMed/MEDLINE, Web of Science, and Scopus identified literature published through 31 July 2026. Evidence was classified by consumed form and reproductive-stage directness and integrated across three regulatory axes: endocrine-stress regulation, immune-redox-neuroplasticity, and gut-brain-metabolic communication. Human evidence includes small randomized trials of standardized saffron, rhapontic rhubarb, fenugreek, ashwagandha, and shatavari preparations, with product-specific psychological-symptom signals, as well as a null Hypericum-Vitex trial. Evidence for plant-rich dietary patterns and isolated bioactives derives mainly from broader menopausal or adult populations. Across studies, reproductive stage, exposure composition, symptom endpoint, and preparation standardization emerge as key determinants of interpretation. Linking symptom clusters with proposed pathway involvement generates hypotheses for prospective phenotype-stratified nutrition trials. Future studies should combine reproductive staging using the Stages of Reproductive Aging Workshop + 10 (STRAW+10) framework, prespecified emotional outcomes, dietary assessment, standardized product characterization, exposure biomarkers, metabotype profiling, and safety monitoring. This framework positions plant-derived nutrition as a testable component of perimenopausal emotional-health research and functional-food development.