Dynamic omniphobic liquid-like anti-fouling coatings have a wide range of applications. However, designing dynamic omniphobic liquid coatings that are highly hard, flexible, and low-cost remains a challenge. In this study, low-cost hyperbranched epoxy resin (HEBP), hexamethylene diisocyanate trimer (HDIT), and polydimethylsiloxane, hydroxy-terminated (HO-PDMS) were used as polymer matrix. Through a copolymerization reaction, a highly cross-linked rigid oxazolidinone structure (OX) and liquid-like molecular coating were obtained. Meanwhile, this unique design endowed the coating with ultra-high hardness (8H), exceptional flexibility, extremely high transparency, and dynamic omniphobic anti-fouling properties. Moreover, the layer can withstand cycles of friction or bending and exhibits excellent chemical barrier properties. Overall, this coating is easily prepared on a large scale and has broad application prospects in different fields such as solar panels, outdoor public facilities, and flexible display screens.