Azimut Fuel Capacity

Do you possibly have the original Italian manual, and if so could you post the exact statement published in it?
Your statement which I'm quoting doesn't make a lot of sense - if nothing else, because fuel is sucked and not pumped, from the tanks to the engine injection pump.

Anyway, my guess is that the rationale behind such recommendation could be the risk of sucking air rather than fuel, hence stalling the engine(s).
I mean, of course there are internal dividers inside the tanks, to reduce fuel sloshing to a minimum and in turn keep the pickup point always submerged till the last drop of fuel (don't take me literally on the term "drop", of course!).
But in heavy seas, a very low fuel content could be moved away from the pickup for long enough to leave the pickup dry, hence sucking air from it.
And this is bound to stall the engine, hence needing to prime it in order to restart it.
Not exactly the most pleasant thing to do, in heavy seas and inside a hot engine room!

Another possibility is what CR mentioned in his post #2, but usually the very bottom part of the tank is even lower than the pickup, precisely to avoid sucking any garbage. And the fuel quantity under the pickup that this area can hold is trivial - like 20 or 30 liters, when talking of a 2800 liters total capacity. Not even worth mentioning in the manual...

Well, as you know I'm not familiar with the documentation normally supplied in the US, aside from having learned here that it can be hit and miss, or even not available at all.
I guess we could see this as yet one more reason for trying to get hold of the original one, because aside from being mandatory on any CE-certified boat (hence necessarily existing, in some builder's database), it's less likely to include any puzzling translations...

But before the OP asks, aside from being available to help with the language, sorry but I don't have the manual myself.
And I believe the builder would only supply it to recognizable/registered owners of any given boat/model, or to their dealers.

Haha, guilty as charged for not having thought of the ...romantic flavor attached to sucking!

I m kind of surprised nobody has asked if there is a way to check fuel levels. No, I don’t mean an electric fuel gauge no matter how fancy it is. I mean either sight tubes if the tanks are high or a dipstick if the boat has keel tanks. I believe either are a must have

Sure you can fill the tank till They burp which in any civilized country will get you in trouble

being a new boat with electronic engines there must be flow meters with totalizers. Keeping an accurate fuel log of what the mains and the gen have burned is pretty easy. Seamanship 101

before leaving download the fuel curves for the engines so you can double check the fuel meters.

I have to say that using sight tubes or dipstick plus a fuel log, I have never Had any issues

Agreed, but you must be used to some remarkable megayacht if you think that filters and pipes can hold 74 gallons of fuel...

I'm not sure to see the difference with what I said in my first post of this thread...