First, visit your website backend an try to do with Elementor what is triggering the WAF block. After a couple minutes, go to Cloudflare Dashboard > Security > Events, and find the event corresponding to that action (it should have your IP address and the Elementor path in it). Then find “Rule ID” on the event, and hover your mouse to copy the ID number to clipboard.
In the second screenshot, where it says “Allora…”, mark the second option “Ignora regale specifiche…”. At the next screen you need to enter the rule number you copied.
Also in the second screen, change the operator to “contains” and just use the word “elementor”.
As can be seen in the last screenshot, this block comes from a Custom Rule intitled Country Block. Edit that rule and exclude the Elementor path from it, or your IP address if it is a fixed IP address.