I just found the solution to my problem. Here is the working code:
// Change Post Content Type
add_filter( 'acf/get_valid_field', 'change_post_content_type');
function change_post_content_type( $field ) {
if($field['type'] == 'wysiwyg') {
$field['tabs'] = 'visual';
$field['toolbar'] = 'basic';
$field['media_upload'] = 0;
}
return $field;
}