How to create custom column for meta field

Use tab "Meta" in the table tools popup.

Also you can add it by code. Use next code in file functions.php:

add_action('tableon_profile_extend', function($profile, $action_name) {

    $profile['hmeta_1'] = [
        'title' => TABLEON_Vocabulary::get('Meta 1'),
        'order' => 'asc',
        'display' => false, //display in fields list in the settings
        'action' => function($post_id) {
            return get_post_meta($post_id, 'meta_1', true);
        }
    ];

    return $profile;
}, 10, 2);

add_action('tableon_profile_extend', function($profile, $action_name) {

$profile['hmeta_1'] = [

'title' => TABLEON_Vocabulary::get('Meta 1'),

'order' => 'asc',

'display' => false, //display in fields list in the settings

'action' => function($post_id) {

return get_post_meta($post_id, 'meta_1', true);

}

];

return $profile;

}, 10, 2);

Trough code you can use custom columns in such shortcode [tableon id=49 columns='id,title,__price,hmeta_1']

Also for some tables it is possible to modificate results in the table cell:

add_action('tableon_meta_data_cell', function($value, $meta_data, $post_id, $table_id) {

    if ($meta_data['meta_key'] === 'meta_1' AND $table_id === 21) {
        $value = floatval($value) * floatval(get_post_meta($post_id, 'meta_2', true));
    }

    return $value;
}, 10, 4);