Man, that's a tough find, tbh. Luckily they announced a sequel recently, so there's that. :)
In the meantime, I'd recommend the following:
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Newer Monster Hunters (World or Rise): Gameplay wise the closest one I've come across so far.
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Elden Ring: I mean... Kind of? Similar Fantasy world, character building, even somewhat similar plot (in my opinion). Obviously it's more FromSoft than DD, but I think it's worth a comparison.
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Dragon Age Inquisition: Now, I get that this one's kind of far fetched, but I mean it. Especially the freedom of character building (except locking into a class at character creation), traveling with npc companions (tough with more personality) and the general fantasy-world vibe
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Shadow of the colossus: If you're mainly into climbing huge monsters and defeating them (primarily) that way, this is one game I would greatly recommend! Tough, this gameplay, a stamina system and the vague fantasy setting are the main comparisons.
Bonus: I read somewhere that with a plethora of mods you can nudge Skyrim more in a DD direction (and who would be surprised about that), but I don't know any pointers on that one. Google might help, tough.
Hope this list is somewhat helpful :D Maybe you could describe what you liked about DD?