How to avoid loading wp-load.php from external php scripts?

Pretty much wp-load.php is the only way to go. I don’t think there is really another way to load the WordPress functions safely…

You can account for path variations by recursively including it from any file where you need it though… eg.

function file_find_require($file,$folder=null) {
    if ($folder === null) {$folder = dirname(__FILE__);}
    $path = $folder.DIRECTORY_SEPARATOR.$file;
    if (file_exists($path)) {require($path); return $folder;}
    else {
        $upfolder = file_find_require($file,dirname($folder));
        if ($upfolder != '') {return $upfolder;}
    }
}

$rootpath = file_find_require('wp-load.php');