I have used Jessandra/Jessessandra, Jessinald, Jesstancia, Jessentina, Jessanca, Jesstoria, Jessody, Jesselia, Jessolet, Jessilda, Jessephine, Jessevieve, Jessentine, Jesselaide, Jessalie, Jesselope, Jessatrice, Jesselia, and many more. Just because she introduced herself saying her name was easier to remember than the other two that had just introduced themselves. Admittedly I can't remember their names.
You could always throw on a hyphenated middle name. She's no longer Jessica, she's Jessica-Anne.
I have a short full name, think something along the lines of "Sam Dal" (it's not, but same vibes), a lot of people ask what Sam is short for, but the answer is nothing, my legal name is just Sam. My friends will call me "Samuel Jay Dalford" as running joke. Made additionally funny because it's a masculine name and I'm not a man.