Answered: edit answer to accepted answer in schema

How can I modify schema so that the answer directly becomes the best and chosen answer without choosing it

So you want the schema to return the answer as if it was chosen, even if it wasn't. This is an odd request, but here it goes :)

1. Edit your qa-theme/<your-theme>/qa-theme.php file

2. Add or merge this function:

public function initialize() {
    parent::initialize();
    if ($this->template === 'question' && !empty($this->content'a_list']'as'])) {
        $this->content'a_list']'as']0]'tags'] = str_replace('itemprop="suggestedAnswer"', 'itemprop="suggestedAnswer acceptedAnswer"', $this->content'a_list']'as']0]'tags']);
    }
}

Note I'm just turning into accepted the first answer only, as a failsafe.