Three dragons dynamic

Hi just wondering if arcs quality chance to shock on hit with lighting damage will still apply? And if not if I add fire damage wi it apply to that

Shock duration is determined by the amount of associated damage you did in the hit that triggered shock relative to monster max health.

Three dragons changes the associated damage from lightning to fire, so shocks will still trigger with chance to shock and on crit but they will last 0 seconds because you did no fire damage. Unfortunately, it isn't possible to add fire damage to lightning spells, except by converting with avatar of fire, but you lose half of your damage that way.