The terms, as far as I'm aware, are "plot-driven" and "character-driven". By that same token, it's worth noting that these terms are not universally accepted terms of anything of the sort. People disagree all the time over what they mean, and by people, this includes literary critics, writers, etc. On top of everything else, the medium of a story affects how things lean or are perceived as well.
In general though, "plot driven" stories are the ones that focus on "the plot" and where the characters are intentionally crafted to fit whatever the plot is. These stories will generally focus more on the events than the characters, and character interactions will generally serve the purpose of driving the plot forward more than showcasing relationships or anything like that. In extreme cases, the characters are so obviously plot devices that they don't feel like people at all.
"Character-driven" on the other hand, focuses on the characters. The focus is on their relationships, interactions, growth, thoughts, feelings and important moments. Character driven stories may have more or less of a plot, but the plot is simply not the focus of things. In extreme cases, the focus on the characters can be so high that the story doesn't feel like it's actually going anywhere at all, or even exists, or, it suffers from major plot holes and whatnot as the writer is so focused on their characters and the scenes they want them in that they fail to pay attention to the overall context.
Generally speaking, neither extreme is good for stories, which means it's not good for VNs either on average. It's different for games though, because games can be entirely gameplay focused, so they don't really fit into either of those labels and basically just don't need to have a story at all.
Hentai adds its own layer of complexity here, because now there's smut in the mix, so you have "smut-driven" stories and games, which prioritize the sex over everything else, and everything in the story world is warped around making that sex happen. Like the other two things above, extremes of it are, for example, a loose collection of sex scenes with barely anything stringing them together, while the characters are just a mixture of smut tropes put together behind a name.
The thing to note here, besides the fact that these concepts don't have fully agreed on definitions, is that they're subjective in their importance. People enjoy things differently, so one type of story might be great for one person and terrible for another, without any objective distinction between them. Not to mention that most if not all people here are not literary critics or any kind of experts and most haven't even dabbled in any story writing themselves to really make a distinction between concepts beyond the surface levels. They'll throw around these words, sometimes without even really understanding them, and mean them as praise or critique, depending on their personal preferences.
In other words, you really should take such comments on F95 with a grain of salt.
To give some examples of games and whatnot here.
Brainwashing with Tentacles R - This would be a smut driven game. There's characters, and there's a vague story... but it all exists just to allow the sex scenes to happen and don't really matter beyond that.
Turning the Page - This would be an example of character driven story. There basically isn't any big plot here and the focus is on the characters. There's plenty of smut, but there focus is on the character interactions themselves and the smut grows from there so to speak, on top of the fact that it has consequences for the smut. That said, this applies mostly for what some call the main branch of the VN. The latter updates kind of dropped the ball on quality in several ways.
Eiyuu Senki - This is what I'd give as an example of a plot driven H-game. You can literally remove all the sex scenes out of it and it wouldn't change anything, and the character interactions and so on are primarily driven by the plot of the game more than anything. Not to an absurdly extreme degree, but enough so that to me at least, it felt pretty noticeable.
In all three of those examples, it's worth noting that this is basically just my opinion and it's not necessarily fact. I may have done my own dabbling in writing and whatnot, but I am no published author, and even if I were.... Well, being successful doesn't necessarily make you a master in all things.
