Hello,

Unfortunately, there is no option in Theme Settings to make the sidebar menu categories open when click a link on the mobile bottom navbar.

You can find the button options that are available for the mobile bottom navbar under Theme Settings >> General >> Mobile Bottom Navbar.

Screenshot for Clarification: https://ibb.co/7tRY5c6

You can use the mobile menu button from the options to add the mobile menu burger element in the mobile bottom navbar. It will display the complete sidebar menu.

Best Regards.