Based on this request:

Assumptions:
The calculations below will follow the following assumptions:
1. Amber is lv90.
2. The enemy is one lv90 hilichurl.
3. The weapon considered will be:
- R5 Sharpshooters Oath 3★
• No charged attack will be considered
- R5 Messenger 3★
• No charged attack will be considered
- R5 Slingshot 3★
• The attacks will be simulated to fly for less than 0.3 second, allowing the passive to proc everytime
- Rust
- R2 Prototype Crescent
• Will be assumed the +45% attack passive is active from hitting weak spot.
- R2 Viridescent Hunt (BP Bow)
• Will be assumed the passive proc once in the simulation
- Blackcliff Warbow
• Will be assumed the +36% attack passive is active from killing enemies.
- Compound Bow
• Will be assumed the +20% attack is active.
- Skyward Harp
• Will be assumed the passive proc 2 times in the simulation
- Amos' Bow
• All the auto attack will be simulated to fly for 0.2 seconds, giving it +16% damage.
4. Talent lv6, C0.
5. It'll be assumed that all of the hits crit.
• The crit goal will be 60%, anything above that will be considered an "overflow".
Results:
Stat overview:


Damage overview:


Putting all the numbers together from best to worst, and we have:

I also try it out with Fischl and obtained the exact same result:
Edit: Thanks to Tatiana for pointing this out!
Apparently Slingshot is very slightly better than rust on this one!

P.S. Please note that this calculation assume each weapon's passive at its best state. For example, Rust will outperform Blackcliff by ~10% if the passive is not active.


