Code:
alias vartest {
  echo -a Setting % $+ vartest.blah to 123
  set %vartest.blah 123
  echo -a % $+ vartest.blah: %vartest.blah
  echo -a Calling vartest.a
  vartest.a
  echo -a % $+ vartest.blah: %vartest.blah
  unset %vartest.blah
}
alias -l vartest.a {
  echo -a (Called alias) Setting local var % $+ vartest.blah to 123456
  var %vartest.blah = 123456
  echo -a (Called alias) % $+ vartest.blah: %vartest.blah
}

You can have two (or more) variables with the same name, unlimited local and one global.