Just 2c worth here.
Who buys electrics? Riders with means, and commuters. Commuters value storage. Zero 1, Energica 0.8 (passing score), HD 0 (fail, but still love my LW for what it is, not what it is not).
Owned an S and later an SR/F, later modified the SR/F with the risers and lower pegs.
Later still acquired an SS9+. The step up in ridability, range and comfort, and quality was significant for me. Now I never think twice about a 100 mile ride. Another big plus for Energica is better suspension for rough rural roads. If your roads are smooth this may not matter.
The charging differences might be an issue. Zero has no L3 DFC charging but OTOH Zero has faster level 2 charging - YMMV, depends on where you ride and your goals. Slow L2 charging is an issue for Energica in my environs in the southern Appalachians.
Again just IMO, both the HD and Energica are better than the Zero in terms of build quality, brakes, and feel (subjective sorry), with the big exception of Zero's superior luggage options, especially compared to HD's nil options, HD got that wrong.
(So why do I have a LW? I do like this one trick HD pony. It's a blast to ride and of course aesthetics are in the eye of the beholder, I like the look.)
