Both individual weapons and deployable weapons are pre-defined game elements that have been developed by Novaquark.
"There's currently no plan to create a voxel editor to develop character weapons.
At the moment, character weapons are planned to be mesh-based, and defined by developers.
The Dev team has already a lot on her plate with our current goals. Maybe far in the future, but we can't promise anything for now." 
At the moment, the ability of designing and crafting customized weapons related to a specific faction or organization is not planned. Designing and building constructs (spaceships or stations) involves voxels, making construct customization possible for players. On the other hand, crafting enables players to make gear and Elements. Those are non-customizable 3d models (meshes). It would require to make a 3D modeling tool inside Dual Universe to enable players to customize their gear and it would represent a tremendous amount of development time. Moreover, the dev team prefers to keep some control on the artistic vision for the game.