George's look is based on the original Bow's design from She-Ra: Princess of Power (1985) and his name is a reference to Bow's original voice actor George DiCenzo.
The Elberon Vase, depicting She-Ra riding a dragon, refers to a location from The Laughing Dragon (1985). In that story, She-Ra did indeed meet a dragon in the village of Elberon. In the reboot series, this location was previously mentioned in The Sword: Part 1 (2018).
Serenia is explained to be a mythical First Ones Hero. In Something Old, Something New (1986), Serenia was a location described as the one place that kept all of Etheria in balance.