I think what you mean are the Decal Textures of an Weapon Impact.
Such as the Impact Crater Texture of an Nuke in this Case.
Decals have an Duration Variable which can be set inside of the CreateDecal Function.
If the Duration is set to 0 the Decal Texture doesn't Show Up.
--- Creates a decal with supplied parameters. The decal is visible only to armies allied to `army`.
---@param position Vector
---@param heading number
---@param textureName1 FileName
---@param textureName2 FileName
---@param type DecalType
---@param sizeX number size on x axis in game units
---@param sizeZ number size on y axis in game units
---@param lodParam number distance in game units before the decals disappear
---@param duration number lifetime of the decal in seconds, 0 for infinite
---@param army Army
---@param fidelity? number
---@return moho.CDecalHandle
function CreateDecal(position, heading, textureName1, textureName2, type, sizeX, sizeZ, lodParam, duration, army, fidelity)
end
Alternative the CreateDecal Function of each Weapon Code could be Out commented, which deactivate them fully Ingame. However a Mod which deactivate all Weapon Impact Decals in the Game doesn't exists as far as I know. It is possible in General but complex.