Game doesnt know what you want so the arrow system wont work really

Your weapon basic attack is completely separate to your skills damage so you have to work out

1. does the weapon do more basic attack damage than the one I am holding and do I even care
2. does the weapon improve my skills damage/passive stats as you may not even use basic attacks

I only play Geomancers who get 100% Cooldown so they can spam every skill with infinite charges so basic attacks become useless so therefore any weapons basic attack is irrelevant only what stats it gives which is: Crit%/Crit damage/Additional damage/Cast speed are the best stats for any skill based build

So yes you have to manually work it out