This study explores the probiotic potential, immunomodulatory capacity, and safety of Lactiplantibacillus plantarum and Enterococcus faecalis strains isolated from the intestinal tract of the edible terrestrial snail Cornu aspersum maxima. Although host-microbe interactions are well studied in vertebrates, such research remains limited in invertebrates, particularly snails. To address this gap, 12 lactic acid bacteria strains were isolated and screened for tolerance to the defense mechanisms of snails and probiotic-associated traits, followed by machine learning (ML) predictions of immunomodulatory potential. According to results, 10 strains exhibited high tolerance to the external and internal defense mechanisms of snails (pedal and gastric mucus, gastric juices, low gut pH) in association with increased autoaggregation and hydrophobicity values and were predicted to have 100 % probability of eliciting immunomodulatory activity in vivo. Five strains, the L. plantarum Spp1 and Spp11 and E. faecalis Spp3, Spp8, Spp19, were selected for in vivo evaluation. Strain-specific immune responses were observed, with some strains mainly induced cellular immune responses, such as chemotaxis and phagocytic activity of hemocytes, while others also induced humoral responses. However, safety evaluations revealed that certain E. faecalis strains exhibited antimicrobial resistance or induced inflammatory reactions. Only two strains, the L. plantarum Spp11 and E. faecalis Spp19, were validated as safe and effective immunomodulatory probiotics in vivo. Overall, this study provides a comprehensive comparative analysis of the functionality of probiotic Lactiplantibacillus and Enterococcus strains in snails. These findings advance our understanding of snail-microbe symbiosis, particularly in the context of host-probiotic interactions, and support the use of C. aspersum as a valuable invertebrate model for probiotic research.