Introduction The search for new therapeutic agents for the management of diabetes mellitus type 2 (DMT2) and neurodegenerative disorders coupled with the rising number of patients suffering from these pathologies have attracted much interest. Traditionally, extracts from medicinal plants have been used to manage a number of ailments and still remain a potent source of new therapeutic agents. Methods Therefore, the present study was undertaken to evaluate the in vitro antioxidant and enzyme (acetyl cholinesterase (AChE), butyryl cholinesterase (BChE), tyrosinase, α-amylase, and α-glucosidase) inhibitory potential of three medicinal plants (Cupressus sempervirens, Artemisia absinthium, and Lippia triphylla). The phenolic composition of the ethanolic extracts was also characterized using reversed-phase high-performance liquid chromatography (RP-HPLC). In silico molecular docking was used to investigate the possible interaction between active compounds and the studied enzymes. Results C. sempervirens showed the highest inhibition rates against AChE, BChE, α-amylase, and α-glucosidase (2.47 mg galantamine equivalents (GALAE)/g extract, 2.98 mg GALAE/g extract, 1.61 mmol acarbose equivalents (ACAE)/g extract, and 1.86 mmol ACAE/g extract for respective enzymes). The plant extracts showed antioxidant power in the following order C. sempervirens > L. triphylla > A. absinthium. Protocatechuic acid, (+)-catechin, apigenin, and chlorogenic acid were identified in all the plant extracts. The best docking pose obtained for each bioactive compound against the enzymes was mostly stabilized via hydrogen bonds and pi–pi stacks. Conclusion This study provides insight into the antioxidant capacity and the inhibitory potential of these medicinal plants against key enzymes linked to DMT2 and neurodegenerative disorders.