Eco-friendly biocomposites were prepared from poly(lactic acid) (PLA) plasticized with polyethylene glycol (PEG) and reinforced with Moroccan sugarcane bagasse fibers at 5, 10 and 15 wt%. The aim was to enhance PLA ductility through PEG incorporation while valorizing locally available lignocellulosic residues. Two processing methods, injection molding and melt extrusion additive manufacturing (MEX, 3D printing), were employed to investigate the influence of manufacturing method on the morphological, thermal, rheological and mechanical properties of the composites. Thermal analysis confirmed that PLA maintained its stability within the processing temperature range, supporting its suitability for MEX. Morphological observations revealed improved fiber dispersion and reduced porosity in injection-molded samples, whereas MEX-printed parts exhibited visible interlayer voids. These microstructural differences explained the superior tensile strength and modulus of injection-molded specimens compared to MEX ones.