All of the fittings that you marked 1 or 2 appears to me to be crimp on SAE 45º Flare Fittings. They could also be JIC 37º Flare Fittings (the 2 do not mate together correctly) but as yours look to be made from brass, my money is on the SAE 45º Flares. Yes, the hex part of this hose fitting usually swivels.
If this plumbing is to feed the pump that moves fuel from one tank to the other in order to balance the tank contents, I doubt that the bulge of fittings on the left hand side is a check valve. Wouldn't you want the ability for fuel to move in both directions? The pump reverses.....right!
Either the SAE or the JIC fittings are about as good as it gets (and remain modern) for the low pressures of a fuel delivery system. Perhaps if you spent some time with Eaton's Aeroquip catalog you will understand things better.
https://www.eaton.com/ecm/groups/public/@pub/@eaton/@hyd/documents/content/pct_479318.pdf
My small fuel hose of choice remains FC-234 AQP (see page 25) as it's A1 rated and can be used with reusable fittings (page136 -147). Using these you can easily get the total hose length right.
Parker Hannifin (the guys who make Racor stuff) likely have similar products. I for one, would not use push-on hose/fitting products for fuel delivery.
Call me crazy, I'll stick with Eaton.