The counterpart of array_column(), namely create an array from columns, can be done with array_map() :

<?php

// Columns
$lastnames = ['Skywalker', 'Organa', 'Kenobi'];
$firstnames = ['Luke', 'Leia', 'Obiwan'];

// Columns to array
$characters = array_map(
    fn ($l, $f) => ['lastname' => $l, 'firstname' => $f], 
    $lastnames, $firstnames
);

print_r($characters);

/*
    [
         0 => ['lastname' => 'Skywalker', 'firstname' => 'Luke']
         1 => ['lastname' => 'Organa', 'firstname' => 'Leia']
         2 => ['lastname' => 'Kenobi', 'firstname' => 'Obiwan']
    ]
*/