Yes you can use Elementor and WPBakery at the same time. But I WOULD NOT suggest using 2 page builder in the same website, as it will affect the performance, speed & plugin conflict of the website.
The reason is if your website has 2 page builders installed, your website will load extra CSS and Java Scripts from each page builder, it will increased the files size and slow down website. Another nightmare is plugin conflict. So I strongly WOULD NOT suggest using 2 page builder in the same website.