Hello Mcn,

Hope you’re having a great day 🙂

Actually, you can do that but you will need Elementor PRO to be installed.

You can follow the steps below to be able to add Modal Box into the Pricing Table button:
1- Create an Elementor Template that contains the modal box that you need to add into the Pricing Table.
2- Go to your dashboard -> Elementor -> My Templates, cope the modal Template shortcode.
3- In your pricing table button text, paste the template shortcode.
4- Put ‘#’ in the URL text and change link targe to “Self”.

Update and click on Preview Changes to see the changes.

I have attached you four images for more clarification, please check them and feed me back if you still have any farther questions.
Image 1
Image 2
Image 3
Image 4