Where are the unmarked vendors of Genshin Impact?

I thought unmarked vendors only sell useless items like cooking ingredients and dishes. Turns out I was wrong, they also less character upgrade mats, ores, artifacts and other useful stuff.

I've found this reddit thread where some vendors are reported by both OP and other commenters. I've created a list from everything from that thread with minor formatting improvements:

  1. Artifact Vendor (Liyue)
  2. Ore Vendor (Liyue)

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  1. Artifact Vendor (Mondstadt)
  2. Double Blacksmiths (Mondstadt)

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  1. Plant Vendor (Windrise)

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  1. Medicine Shop - Bubu Pharmacy (upper-left Liyue): sells Lotus Head for food ingredients 4* ATK, and some other Liyue specialty

  2. Fish / Crab merchants (Liyue Harbour): Crab is one of the ingredient for 5* ATK

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  1. Food Vendor (Liyue, literally right next to the marked food store): they sell 2 Chop suey, which decreases your climbing and sprinting stamina usage by 25%.

  2. Flowers vendor (Qingce Village by the mill): sells Silk Flower and Glaze Lily


Mondstadt region

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  # |  Name   |       Location       | Vendor Items |  Stock Refresh 
 ---|---------|----------------------|--------------|---------------- 
  1 | Shiliu  | Mondstadt            | Artifacts    | 1 week         
  2 | Flora   | Mondstadt            | Flowers      | 3 days         
  3 | Chloris | Windrise (see route) | Flowers      | 3 days         
  4 | Brook   | Springvale           | Food         | 1 day  

Liyue region

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  # |      Name      |       Location       |    Vendor Items     |  Stock Refresh 
 ---|----------------|----------------------|---------------------|---------------- 
  1 | Herbalist Gui  | Liyue Harbor         | Flowers/Food/Recipe | 3 days         
  2 | Zhang Shun     | Liyue Harbor         | Artifacts           | 1 week         
  3 | Jifang         | Liyue Harbor         | Books               | N/A            
  4 | Linlang        | Liyue Harbor(@Night) | Artifacts           | 1 week         
  5 | Shitou         | Liyue Harbor         | Mining Ores         | 3 days         
  6 | Chen the Sharp | Liyue Harbor         | Food                | 1 day          
  7 | Su Er'niang    | Liyue Harbor         | Food                | 1 day          
  8 | Uncle Sun      | Liyue Harbor         | Fish/Crab           | 1 day          
  9 | Uncle Gao      | Liyue Harbor         | Fish                | 1 day 

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  # |   Name    |    Location    |  Vendor Items  |  Stock Refresh 
 ---|-----------|----------------|----------------|---------------- 
  1 | Ms. Bai   | Qingce Village | Flowers/Recipe | 3 days         
  2 | Pops Zhou | Stone Gate     | Food           | 1 day 

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     Name     |  Location   | Vendor Items |  Stock Refresh 
 -------------|-------------|--------------|---------------- 
  Verr Goldet | Wangshu Inn | Food         | 1 day    

Draff will also sell you raw meat and fowl if you catch him during the day in Springvale. Find him standing on a hill with Allan during the day near the houses and windmill in Springvale and you should be able to do it as long as you have completed the quest that involves him and Olaf. At night he is next to a house and won’t sell anything.