Maybe I might be able to give a little insight from a professional stand point! (my degree is in the illustration and design field and currently work as an illustrator)
Visually I think in a composition sense both have perks, but like how you mentioned before, where you post/publish and who your target audience is is a key factor to what design works best. If this book were in a store I definitely think your first/current cover is more of an attention grabber especially to those who are more experienced with / grew up reading traditional "western" novels for lack of a better word (non-asian/eastern novels). However, I've noticed that the online scene is dominated by eastern novels / light novels and that seems to be what gets the most clicks, especially so on sites like this. With that being said your 2nd cover is a bit more in line with what that audience would click in because character centric covers tend to be the draw.
Though if you might allow me to suggest, when creating a cover you'd wan to make sure the character's face is very visible from afar / if the image is small/a thumbnail or have the character doing a big action that takes up a lot of the cover. I'd also try and contrast colors a bit more harshly between the character and background. Often in the industry when making things for websites we will purposfully shrink it down and take a step back to make sure the image is still eye catching and that the focal point is still clear.
Then this is putting aside the fact like someone already mentioned before that AI image covers tend to put a lot of people off - my own personal oppinion/prefrence is that I'd rather click on a novel with a cover that has art drawn by the author who has tried their best to draw their character(s) despite never drawing before than a cover made by AI because I feel more connected to an artwork created by the author since I know that every line, color, and element in that character was created with intention and makes me feel like this is the character that was in the author's mind. Opposed to AI it makes me feel like this is a character that the author settled on, they just randomly generated with different prompts until it got close enough and nothing was intentional except the really generic elements- it just feels impersonal and not as exciting. When AI image covers dominate a site, even poorly drawn covers become more eye catching and more likely to get clicks.