OK, here's what I'm gonna do: I'm going to ignore the alarming age difference between them, so I can review this ship properly.
Depending on their interactions in Moon Rising, they have a sweet dynamic.
I don't ship them, though. If anything, I see their relationship as a mentor/apprentice thing and nothing else.
They are pretty devoted to each other. Darkstalker willing to not enchant Moonwatcher on the spot. And Moonwatcher always trusting him, even after hearing the terrible things he did.
Also, compared to the Winterwatcher and Moonbli scenes in the books throughout, I much more enjoyed the cute interactions between Moon and Darkstalker in MR. Most likely, because I find their friendship more genuine and sincere than any romance that was shoved Moon's way.
If anything, their friendship was just as beautiful and tragic as Darkstalker's and Clearsight's romance.
Speaking of Clearsight, there's one thing that still baffles me.
At the start of the second arc, Darkstalker went on and on about how Moonwatcher reminded him of his girlfriend. So, why didn't he enchant Moon to turn into Clearsight, instead of Fierceteeth?
Sure, it would've been HELLA creepy. But, it would also be easier, since Moonwatcher was an almost perfect replica of Clearsight?
And, I know Darkstalker sworn to not use magic of Moon, but he also enchanted Clearsight once, so it wouldn't have been that low for him to do so. I dunno, it just makes more sense than enchanting some random NightWing you just met to turn into your ex.
Pros: Final thoughts, the ship isn't completely terrible. Still, I don't see it anywhere near romantic. In my opinion, I wished their mentor/apprentice relationship was explored more, because to me, Moonwatcher didn't have a strong enough reason to trust Darkstalker after hearing the things he done.
Cons: There are good parts of this ship, but there's no doubt that it can get toxic really fast. Darkstalker did manipulate Moonwatcher, which can lead to psychology abuse, if that's even a thing.