I've looked into hand-crank generators, and most that are sold seem to be complete trash, having plastic gears, horrible gear ratios (marathon spinning), cheapest DC motors.
They are usually only able to power old android phones at best and are most suitable for cellphones of the previous decade.
One hand crank that does stand out is the one that produces 120V ("pocket socket"), it appears to also be decent handheld size and not a child hand size, the issue is too much power conversion DC-AC-DC, or worse AC-DC-AC-DC, while it seems to be sufficient to power 1A requiring devices, I have not seen it being used with 2.4A bricks, and whether it can produce enough power, the manufacturer does not seem to list the wattage its capable of, so its probably bad.
Third option is Chinese handhelds designed "for military" that are super cheap on alibaba in bulk, but become 3X more expensive on aliexpress/amazon, $170 for 30W one, made of metal, but the specs while promixe 3A max, say that nominal is 1.5-2A, probably meaning that you have to spin it super fast, meaning gearing sucks (low torque).
Any suggestions? Is there a high torque gearing that provides nominal ~30W that would be capable of 2.4A 5V quick charging?