Can I use Elementor Pro on WordPress.com?

Yes.

Elementor y Elementor Pro funcionan en sitios Web from WordPress autohospedados (WordPress.org) y también en WordPress.com.

Please note that if you use WordPress.com, you will need the Business Plan to use Elementor.

References:

https://en.support.wordpress.com/com-vs-org/

https://en.blog.wordpress.com/2017/08/07/wordpress-com-business-now-supports-plugins-and-third-party-themes/