But the weapons skill does not apply to the weapon itself, it applies to the total element damage.

One weapon with 1k atk and 3.5% skill and 9 weapons with 1k atk and no skill but of the same element would be 10k base atk. For the bonus, 10k*1.035 = 10350

I have one question thou.
Is it better to lb the event weapon or keep them separated to fill my weapon grid?