The fact that they both can take a package variables as an argument doesn't make them related in any meaningful way.

local is about aliasing package globals

No. For example, my %h; local $h{x};. It's about making temporary backups of some values.

our creates a package global

No. our creates a lexical variable (that's aliased to the specified package variable).

Simply mentioning the package var is what creates it.

$ perl -le'      print $::{var} // "[undef]"'
[undef]

$ perl -le'$var; print $::{var} // "[undef]"'
*main::var
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