When discussing Dracula vs. Cthulhu, people seem surprised when I say it’s science-fiction and then talk about spaceships and time travel. So I’ll say it, again! Dracula vs. Cthulhu is science-fiction horror! So, yeah, don’t be too surprised if it has spaceships and time travel.
This is part of the reason to do such a story, right? If I was going to write a story where Dracula was just another Gothic monster, who would care? But the je ne sais quoi is the “vs. Cthulhu.” And Cthulhu? He’s on the sci-fi end of Lovecraft’s works. Further, I process both Cthulhu and Dracula through the lens of my interpretations and preferences. I think Lovecraft was at his best when he was at his most science-fiction-y.