The present work proposes the use of a triple-orifice spinneret for producing hollow fibres (HFs), exploring the use of an external fluid to modify the gas transport properties of the resulting membranes. In addition, a method that includes the crosslinking step within the dry-jet/wet-quench spinning process, using a crosslinker solution as bore fluid or as external fluid is proposed. The protocol was applied to the preparation and simultaneous modification of polyimide-based HFs. The HFs were characterized by investigating the changes of the morphology and gas permeo-selective properties as consequence of the spinning conditions.