I would say that Davis has better one punch power while Inoue throws consistently more powerful shots. Also, Inoue has power to the head and body while Gervonta is more the headhunter type. It is Inoue for me.
Raw power I'd say Tank, his style sees him sit down and load up more, often unleashing big shots from a slight crouched position. Inoue while has raw power relies more on speed, precision, timing, setting up his opponent, he's a more complete and effective puncher in my opinion hence why he can literally KO you with either hand, with any punch, to head or body. I don't think I've ever seen a fighter hurt a guy to the body as much as Inoue, his body shots seem to be his most dangerous punches. Raw power isn't everything even when it comes to being a good puncher. I think aspects like set up and delivery are just as important aspects of what makes a dangerous puncher. Between the two I see Inoue as the more dangerous puncher even though he may have less raw power.
They both are pretty extraordinary when it comes to p4p power. I slightly favor Tank with the heavier hands.
Inoue = hurts guys his own size and bigger Davis = struggles to KO smaller dudes like Cruz who made him his female dog
I just watched all Inoue KOs vs Gervonta Davis KOs, Inoue had 7 one punch KOs in 22 fights and Tank had 5 in 27 fights. Not the only measure, but it's a decent measure. Of course in Inoue's case three were to the body.