In reply to Charlotte.

Hi Charlotte, I apologize for any issues you are running into! Block Visibility is not designed to work within the Elementor editor, only the WordPress Block (Gutenberg) Editor.

That said, I am not aware of any direct conflicts between the two plugins. If you wouldn't mind opening a support ticket in the plugin support forum (https://wordpress.org/support/plugin/block-visibility/) and providing a bit more info on the conflict you are seeing, I will begin investigating asap!