On the ublock origin UI you can click a little icon in the toolbar pull up the settings for that page. There is a little icon you that shows you whether it is enabled or disabled both in the toolbar and in this settings page. Clicking it in the settings page toggles the state for that page which is retained next time you visit.
When you change the state a little refresh icon appears right behind the status icon indicating that the state of the page as shown doesn't match your setting. Clicking it reloads the page.
You could reload it automatically at state change but this might break whatever the user is in the middle of doing.
You don't have to have this feature but it is handy that the reminder that the page is out of sync is a button to fix this and that it is half an inch from your current mouse position.
I created an extension that flushes all cookies and local storage for the current domain; it then reloads the page so you appear to be a fresh new visitor.
Can you explain why you'd want to do this? At first blush it seems like a terrible idea to allow extensions to reload pages.