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Given the global transition to a circular economy, there is a growing demand for sustainable, bio-based alternatives to synthetic materials used in construction. This study investigates the possibility of developing sustainable hemp fiber composites with biopolymer binders (chitosan, starch, and nanocellulose) and examines their applicability as acoustic insulation wall panels. Four types of composite panels were synthesized using the husk-free fibers of industrial hemp (Bialobrzeskie variety). The binder material contained 4% chitosan and 2% chitosan, while potato starch and nanocellulose (CNF) were added in two different variants. The 2 cm thick panels were produced by pneumatic spraying followed by hot pressing at 100 °C. Tests included three-point flexural strength measurement (EN 310 standard), thermal conductivity estimation (ISO 8301), and determination of sound absorption efficiency (α) using the Kundt impedance tube method. The panels were shown to have low to medium density, i.e., between 0.264 and 0.282 g/cm³. Acoustic analysis showed good high-frequency performance with the highest absorption coefficient recorded in the 3125–4000 Hz region α ≈ 0.9; this makes it quite effective for sound reduction at speech frequencies. In contrast, low-frequency performance (≤500 Hz) was observed to be poor (α < 0.2), which is expected from a porous fibrous material without air gaps. Thermal conductivity ranged from 0.047 to 0.052 W/(m·K), and heat resistance (R) varied between 2.41 and 2.79 m²·K/W, indicating good insulation properties. CNF-reinforced panels showed increased flexibility and energy dissipation, while chitosan-starch bonded panels reached a maximum flexural strength of 0.46 MPa.