• A versatile surfactant-free emulsion construction strategy is proposed to customize functional hydrogels.
• The synergistic emulsification mechanism between amphiphilic polymers and MXene is comprehensively elucidated.
• Programmable functional structures confer hydrogels with excellent EMI shielding and water evaporation performance.
• The hydrogels exhibit high EMI shielding efficiency (~64 dB) and superior solar evaporation rate (~3.5 kg m⁻² h⁻¹) with salt tolerance.