Hashtags are useful for promotion on Twitter, Instagram, Facebook and Youtube,  but is there any benefit to using them when submitting to the stock agencies?

Nope

Why would you bother?

and nope too 

Interesting idea, is that allowed? I wonder about searches finding them in titles or keywords?

I'd also wonder if it is really worth the effort, I'm not going into studying that, just a personal lack of interest, but maybe someone else has some input?

I just did three searches for single words beer, wine, cat then added the #
The results are the same total images and the order of images is just slightly different almost un-noticable.

Quote from: PhotoBomb on June 01, 2022, 18:39
I just did three searches for single words beer, wine, cat then added the #
The results are the same total images and the order of images is just slightly different almost un-noticable.

I'd expect that but I wonder about the larger WEB itself? Or do hashtags lead to the subject and not to stock photos. I'm not chasing this one. 

Quote from: Uncle Pete on June 01, 2022, 22:56

Quote from: PhotoBomb on June 01, 2022, 18:39
I just did three searches for single words beer, wine, cat then added the #
The results are the same total images and the order of images is just slightly different almost un-noticable.

I'd expect that but I wonder about the larger WEB itself? Or do hashtags lead to the subject and not to stock photos. I'm not chasing this one. 

ditto

Quote from: Uncle Pete on June 01, 2022, 22:56

Quote from: PhotoBomb on June 01, 2022, 18:39
I just did three searches for single words beer, wine, cat then added the #
The results are the same total images and the order of images is just slightly different almost un-noticable.

I'd expect that but I wonder about the larger WEB itself? Or do hashtags lead to the subject and not to stock photos. I'm not chasing this one. 

Why should it make a difference? Hashtags, unless I am completely misunderstanding something, only serve a purpose within the platform they are used on and only if the platform supports hashtags.
Like, take Facebook for example or instagram. You make a post and you add a word with a hashtag. The hashtag becomes a clickable link where people can click on and then get shown all posts with the same hashtag. It's basically like a custom category.
How would adding a hashtag to a stock photo serve any purpose on the web? It's not like you click on a hashtag on Facebook and suddenly have a stock photo from a microstock agency shown up. Hashtags only work internal. And stock agencies don't support hashtags as such. Using a hasthag in keywords would only make sense if the picture actually showed a hashtag and a customer would search for that keyword.

#NO