Ganyu

Amos' Bow
Provides an enormous amount of DMG% bonus to Charged Attacks. 3 stacks of its passive are guaranteed on her Bloom damage.

Prototype Crescent R5
Assuming she can hit a weakpoint, this bow is competitive with her 5* bows.

Hamayumi R5
A reliable source of DMG boost on normal and charge attacks, buff is further increase by 100% when burst energy is 100.

Early Game Option:
Sharpshooter's Oath
Hits on weakspots are guaranteed to CRIT. Thus, no CRIT Rate is necessary if you're an aim god.

Aqua Simulacra

Thundering Pulse
Excellent unconditional weapon for DPS capability. Its passive is largely wasted due to it providing Normal Attack DMG.

Polar Star
Conditionally excellent if Ganyu stacks its passive by weaving in a Normal Attack before her DPS window (ie. N1EC+).

Skyward Harp

The Viridescent Hunt, Blackcliff Warbow and Hamayumi R5 are all very viable.

<sands> ATK%/EM
<goblet> Cryo DMG Bonus
<circlet> CRIT DMG

CRIT DMG
CRIT Rate
EM
ATK%

1) Normal Attack: Liutian Archery
2) Elemental Skill: Trail of the Qilin >= Elemental Burst: Celestial Shower

The First Great Magic
Regardless of the number of Cryo teammates, this weapon will almost always be best. However, it is not a major change or a must-pull.

Aqua Simulacra
Best unconditional damage focused weapon. Due to a lower Base Attack, Ganyu's damage will scale slightly better with Shenhe's Elemental Skill buff and Bennett's Elemental Burst Flat Attack buff.

Prototype Crescent R5
Assuming she can hit a weakpoint, this bow is competitive with her 5* bows.

Amos' Bow
Provides an enormous amount of DMG% bonus to Charged Attacks. Any team compositions that use them will find Amos' Bow very effective. However, a significant amount of Freeze DPS Ganyu's damage is her Elemental Burst, which it does not buff.

Early Game Option:
Sharpshooter's Oath
Hits in weakspots are guaranteed to CRIT. Thus, no CRIT Rate is necessary if you're an aim god.

Thundering Pulse
Excellent unconditional weapon for DPS capability. Its passive is largely wasted due to it providing Normal Attack DMG.

Polar Star
Conditionally excellent if Ganyu fully stacks its passive by weaving in a Normal Attack before her DPS window (ie. N1EQC+). Will go over 100% CRIT Rate against Frozen enemies with 4pc Blizzard Strayer and Cryo Resonance, thus losing value.

Skyward Harp
Great unconditional damage option. The CRIT Rate stat is not ideal, as it raises the likelihood that Ganyu goes over 100% CRIT Rate with artifact substats against frozen enemies.

Mounn's Moon, The Viridescent Hunt, Blackcliff Warbow and Hamayumi R5 are all very viable.

<sands> ATK%
<goblet> Cryo DMG Bonus
<circlet> CRIT DMG

CRIT DMG
CRIT RATE
ATK%

1) Elemental Burst: Celestial Shower
2) Normal Attack: Liutian Archery
3) Elemental Skill: Trail of the Qilin

Only play Marechaussee hunter with Furina.

Aqua Simulacra
Best damage focused weapon. Ganyu's Elemental Burst snapshots its 20% DMG bonus when near enemies, so ranged on-field DPS' are not a problem.

Elegy for the End
Great for team compositions based on Reactions. Its Elemental Mastery and ATK% buffs are very helpful. The ER stat is great for her, as running ER sands may no longer be necessary in some teams. On others, it can be a loss for her personal DPS but is usually made up for by the gain in team DPS.

Favonius Warbow
Conditionally very good; as Ganyu gets CRIT Rate from many sources, getting its passive off can be consistent depending on the team composition, decreasing ER requirements and thus increasing potential team DPS. Note that it only activates when she is on-field.

Thundering Pulse
Excellent weapon for sub-DPS capability. Its passive is largely wasted due to it providing Normal Attack DMG.

Polar Star
Conditionally excellent in comps that can fully or partially stack its passive by weaving a Charged Attack and/or a Normal Attack into Ganyu's rotation window (ie. N1CEQ) without it being a DPS loss. Will go over 100% CRIT Rate against Frozen enemies with 4pc Blizzard Strayer and Cryo Resonance, thus losing value.

Skyward Harp
Great unconditional damage option. The CRIT Rate stat is not ideal, as it raises the likelihood that Ganyu goes over 100% CRIT Rate with artifact substats against frozen enemies.

Prototype Crescent R5
Assuming she can take the time to hit a weakpoint, this bow is competitive with her 5* bows.

Mounn's Moon, The Viridescent Hunt, The Stringless, Alley Hunter, Blackcliff Warbow are all very viable. Most DPS bows can be viable in comps that use some Charged Attacks.

<sands> ATK%/Energy Recharge
<goblet> Cryo DMG Bonus
<circlet> CRIT DMG / CRIT Rate

CRIT Rate
CRIT DMG
Energy Recharge
ATK%

1) Elemental Burst: Celestial Shower
2) Normal Attack: Liutian Archery
3) Elemental Skill: Trail of the Qilin