While the 6xxx series offers excellent properties, laser welding of these alloys presents challenges related to solidification cracking. The state-of-the-art uses lasers in conjunction with filler wires to alter the freezing range and hence reduce the crack susceptibility. Although this process allows achieving up to 80% joint efficiency, it necessitates a close contact to the material. This negates the key advantages of on-the-fly laser welding. Recent advancements in dynamic beam shaping have shown the potential to revolutionise the welding process. Although this is a very attractive proposition, knowledge about the temporal and spatial response of the process to dynamic beam shaping is yet required. This study implements a multi-kW and CW laser with coherent beam combiner (CBC) and optical phased array (OPA) to modulate the fluence distribution at the microsecond scale. It aims to analyse the solidification cracking susceptibility for a set of individual free-form beam profiles generated in the kHz regime, as well as a set of sequences of beam profiles switched at the microsecond time scale. A self-restraint cantilever hot cracking test, featuring a full-penetration single bead-on-plate weld, was used to evaluate crack susceptibility on AA6082 1.5 mm sheets. Metallography analysis with electron backscatter diffraction was then implemented to link material microstructure to the tested beam shapes. Results are presented to highlight the unique features of the modulated fluence distribution. The talk will conclude pointing out the current approaches to develop a predictive thermo-mechanical model with beam shape intensity distributions modulated in time and space.