Well look at this picture when selected one word, a tiny icon appears and when we click the icon we can directly search the selected word in that website! How many such icon depend on users themselves. For me, I need at least Google, Baidu, Taobao, Zhihu, Longman 5 icons. And you can also design where these 5 icon rank, whether it's vertical or horizontal or N×N or in any other position. It's more convenient than you right click menu. And users could also design whether the search web a new open Tab or just new half window beside the word.
①Which webs to search for this tiny icons refer to;
②Where these tiny icons pose;
③Whether you see the new page in a new open Tab or just new half window beside
"directly search the selected word in that website" that would be CTRL + F or from ellipsis (...) menu, search on page.
to search the web for a highlighted text, using the search engine of your preference: edge://settings/search right-click and select "search the web for..."
to use sidebar, using Bing engine, highlight the text, right-click, "Search in Sidebar for ...."
not everyone wants to see a popup show up everywhere they click or highlight, and right-click (or on touch screen devices, hold with finger) is Not troublesome or hard at all, it's a normal procedure used in all kinds of software and apps. that's why there are extensions, so anyone that wants to have a feature, can install the extension and use it, without affecting other people's experience.