Diana is named so because the name Diana is derived from the Roman goddess of the moon and hunting.
Also! Diana's weapon, the Moonsilver Blade is a "reverse khopesh", making it a stylized scythe, alluding to it being a metaphorical reaping tool, alluding to the harvest, another aspect of the moon.. and also the murder of the Solari elders in her case whom she "reaped".
Bonus art tidbits! Diana's character design utilizes forms and shape language which are antithetical and opposing of Leona's design language. While Leona's design flairs out in many aspects (the Solari symbol, her crest/crown/faceguards, dress, etc) Diana is comprised of inwardly converging circles or ovals (chest guard, gauntlets, dress, etc).
:)