Mood Matrix is a GenAI-powered system that allows designers to input conceptual ideas and generate immersive visual outputs projected onto a two-wall environment. We conducted a pilot study with three pairs of designers working on speculative design tasks to observe how immersive AI-driven visual environments influence creativity, collaboration, and exploration during the design process. This formative study serves as a precursor for further evaluation on projecting GenAI media to guide rapid ideation and stylistic exploration.