This work investigates transverse crack behavior in concrete elements reinforced with hybrid lap-spliced connections of glass fiber reinforced polymer (GFRP) and stainless steel bars subjected to four-point flexural load. To obtain cracking patterns, four sensor technologies are employed. Specifically, six linear variable differential transformers (LVDTs) are mounted on the bottom concrete surface of the specimens; one Epsilon distributed fiber optic sensor (DFOS) is embedded directly in the concrete; besides, three-dimensional digital image correlation (3D-DIC) is applied to the bottom surface, and 2D-DIC monitors one side surface. Consequently, the advantages and limitations of the used technologies are evaluated. Then, numerical models based on a calibration framework are developed to validate the experiments. The results show strong agreement across different measurement techniques and the numerical simulations, confirming consistent trends in load bearing and crack behavior. Furthermore, the validated models are extended to explore untested optimal lap-splice lengths. Consequently, 600 mm is identified as the optimal length under those conditions. However, this value shows significant discrepancies compared to those calculated according to various standards. In addition, positioning splices in an adjacent way can yield slightly performance gains (<5%), while enhancing load redistribution and promoting a more uniformly distributed crack pattern.