Highlighted weapons are free options.
Ganyu's Burst is the main damage source in Freeze teams, therefore Charged Attacks should only be used when the time between using the teams Skills and Bursts allows it. If running Shenhe alongside Ganyu, weapons with CRIT Rate / CRIT DMG stats and/or DMG% are slightly favored.
With (4), it is best to aim close to but not above 45% CRIT Rate.