The code for this appears to already be in the game, if you equip an exotic weapon in the kinetic slot, regardless of ornaments, if you inspect a shader, that shader will also be applied to the exotic weapon (good examples of this include Outbreak Perfected, Suros Regime, Sweet Business, and Monte Carlo)
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Unfortunately, that's what "ornaments" are for - so they can't allow shaders or it harms the sale of exotic ornaments in eververse.