Sucrose build recommendations
Sucrose's Ascension 4 Talent boosts the entire team's EM by 20% of Sucrose's total EM, this is why you want to stack as much Elemental Mastery as possible in her artifacts. As a support, most of Sucrose's value lies on her Ascension 1 and 4 talents, hence leveling her other talents (Normal Attack, Skill, Burst) is not required.
Regarding Weapon Choices
This weapon does not provide any EM, however it overtakes the other weapons on the list when it comes to buffing your team. It offers 48% ATK boost to the character you swap to which is equivalent to 1 main stat. This buffs your DPS more compared to which gives ~44EM, equivalent to only 2 substats.
Is a good option for teams where Sucrose can swirl Electro to trigger its damage-boosting passive. In Electro-Charged teams, she can buff Hydro DMG% as well.
This weapon can be useful if you value the extra energy generation from the passive. You may need to get a few crit rate substats to trigger the passive reliably.
There are some team compositions in which Sucrose's Elemental Mastery is not a priority, such as Freeze teams or an Anemo battery for Xiao. In such situations it's better for Sucrose to use .
Artifact stats priority
em er atk% crit rate, crit dmg