A method for improving mycelial leather replacement compositions includes providing a mycelium material substrate, deacetylating chitin to chitosan enzymatically in a deacetylating unit, treating the deacetylated mycelial material substrate with cationic chlorohydrin in a cationization unit, combining deacetylation and cationization processes to improve the interaction with anionic aqueous treatment using an affinity enhancement mechanism, implementing a homogeneity control unit for ensuring uniform distribution of aqueous anionic treatment, creating bonding between the cationized mycelial material substrate and cellulosic fibers resulting in a positively charged fiber that maintain its charge in aqueous solution and optimizing dyeing processes for dye uptake and color fastness in mycelial leather replacement composition. Thus, the chemical penetration and homogeneous distribution of reactive sites with substantive fillers create a leather-like material in terms of texture, appearance, and performance characteristics.