You could probably fill a page with nicknames for Elizabeth…Liz, Lizzie, Lisa, Libby, Betsy, Beth, Betty, Bess, Bessie, Bet, Bette, Eliza, Elsa, Elsie, Izzy…
The one the leaves me puzzled is how Russians (and other Eastern European cultures) get from Alexander to Sasha.
A 2011 SDMB thread on the topic. TL;DR: “-sha” and “-ya” are commonly appended to portions of a proper name to create a nickname/diminutive in Russian. I’m guessing that one takes the “xa” (or “sa”) part of Alexander / Aleksander, add a “sha” to that, and you get “Little Alexander.”
It’s similar to how Scots get from Alexander to Sandy.
How about Ignatius -> Nacho, but also Iggy
Alexander->Xander->Xandy->Sandy
(My youngest daughter goes to school with a Xander.)
“Elizabeth, Elspeth, Beth, Betsy and Bess,
All went together to take a bird’s nest.
They found a nest with six eggs innit,
Each took one, and left five innit.”
You can certainly say so 
I’m sorry, I’m sorry, but I don’t like being called ‘Eddie Baby’.
Check her backpack for stakes, holy water or crossbows.
So Eddie is a nickname for Burpo?
I should point out that “Jack” is not always a nickname. My father’s legal name - on his birth certificate - was Jack. He also had a first cousin by the same name.
From time to time, he’d receive some quasi-formal mail addressed to “John _____”.
Since the Welsh (not Irish) form of Margaret is Megan, it might have also traveled that route.
On which note, how did Spanish get from “Jesus” to “Chuy”? That’s one that’s always perplexed me.
That’s true of every diminutive. There are people who are just named “Tom” or “Ted,” etc.
According to Wikipedia, it’s Margaret - Meg - Megan. So it’s the other way around
One that I have never figured out is that Italian- Americans of a certain age named “Vincent” go/went by “Jimmy”. Anyone know why?
Could someone explain the path my ex-wife took to get from James (my first name) to Lazy Ass?
mmm
Shorten to the “sús” part, then sound-drift to “Chu”, then diminutive to Chuíto (in PR we stopped there) or Chuín, then shorten that to “Chui”, move the stress back to the u, write it with a “y” at the end because in Spanish ortography that how you most often end a word with an unstressed “i” sound.
Makes me think of the Kennedy men. John to Jack, Robert to Bobby, and Edward to Teddy. How did the last one evolve? I can see Theodore to Teddy, but Edward?
And show did Stacy, originally a nickname for Anastasia, become a man’s name?