If `e` isn't already used by another command or function in your environment, you could do something like this in .bashrc, .zshrc, or wherever you put your aliases:

    alias e='exa -1'
    alias ea='exa -a1'
    alias ee='exa -hla'

Note, that's a number "1" in the first two, and -h here includes the headers, which is different from ls -h, which exa appears to do by default. Other than the one entry per line printing, it's similar to the ubuntu default aliases for ls.