maybe there's no correlation between these, but I'll still say it until someone better than me comes and proves me wrong...
For a website with such a good DR and UR, and with so many RDs and backlinks your organic traffic but - more importantly - the number of keywords you're ranking for (45) is incredibly low.
This tells me that only a handful of pages are ranking (although, I've no idea how many rankable pages your site has, so this might be an issue too), up to 10 if I were to guess, but more like 2-5 which, again, is very little in my newbie opinion..
In this situation, I would probably do something about the other pages (assuming that you do have them) that can be ranked, like for example...
a) build some internal links to them from already indexed pages that get traffic (but only as long as they're relevant, otherwise I don't think it will do you much good)...
b) update the content (although, this might work for normal sites, I'm not sure how you can update the content on adult sites, it's possible that this industry is treated differently to normal niches by google)
maybe I'm wrong again, but from my experience sandboxing only happens the first time a site is made live. In your case, this would be in January 2024 when you first created the site.
Assuming that you've done everything right, back then, but still couldn't rank for months then you could say that you've been sandboxed.
But not ranking / not moving in the SERPs AFTER you have already ranked before is not sandbox anymore (at least not the sandbox effect that I know of), this looks more like an SEO-related issue.
If the DR and UR of your site are genuine (ie. NOT inflated through various black hat tricks like redirects, for example) you should have no problem ranking for A TON more keywords than just 45, and also rank A TON of pages more than the ones that are currently ranking. So, something's not right somewhere...
From your GSC screenshot it looks like something weird / black hat / shady / unnatural has happened starting with August 2025 because the clicks are at the same levels as before even though the impressions have plummeted to basically nothing. And this is not normal...
So it's probably either CTR manipulation or other type of manipulation / weird stuff that's been happening with your site that I can't figure out. Maybe you should demand explanations from your "SEO specialist" about why there is this gap between clicks and impressions.
I was a bit sarcastic by putting SEO specialist in quotes, sorry, I can't help it sometimes

... But seriously, if your guy is really a SEO specialist he should have some answers for you, even if you don't understand what he means. Post them here and one of us might know what he means...
Also, in August there was a big google update, so it's possible that your site's been affected by that update... although... once again, the things I'm mentioning here pertain to normal sites in white hat industries, I genuinely don't know how the adult industry works with regards to google, so all of this text might be just random blabbering at the end of the day, sorry about that!
as I said earlier, I don't think this is sandbox, and if it is sandbox then it's not an effect that I'm familiar with.
But the sandbox effect that I'm familiar with can last anywhere from 3 months to 2 years, but usually between 6 and 9 months, so make with this info what you will...
ask your SEO guy why the clicks are high while there are no impressions since August, and - depending on what he says - either start working on his suggestions to fix the issue, or post his reply here so we can figure out what's wrong and - hopefully - give better replies
yes, but I don't think you're sandboxed, I think there is something on your site that's preventing more of your pages (IF you do have them) from ranking...
It could also be something with google that's stopping your site from ranking as well, but unless we fully audit your site, niche, and keywords we can only guesstimate what the problem could be, so this requires a more in-depth analysis. Tell your SEO guy to look into the situation and offer some explanations, I'd be curious to hear what he says
EDIT: sorry, I forgot to ask this:
what does this mean?
I mean, I know what it means, my question is how do you know which regions you are supposed to rank in? Is your domain local (has location words in it), or do you know where you're supposed to rank in?