Enforce default country setting globally
If you set it here https://example.org/wp-admin/admin.php?page=CiviCRM&q=civicrm%2Fadmin%2Fsetting%2Flocalization&reset=1 it does set the country field correctly if used in create mode form e.g. within a contribution page but not if used in listings mode.
Noting @JonGold made an extension that solves this: https://civicrm.stackexchange.com/questions/20986/show-default-country-and-state-for-public-proximity-search
To upload designs, you'll need to enable LFS and have admin enable hashed storage. More information