It seems like Microsoft is hellbent on adding everything but the kitchen sink to its Edge browser, in an attempt to have it cater to every imaginable use-case. Over the past few months, we have seen the introduction of many new utilities in various channels of the browser, including shopping features, a Word-like Citations tool, Office integration, a Math Solver, and more. One could argue that none of these are core browser features so should be added as extensions, but clearly, Microsoft thinks differently.
Now, it seems that the company is working on adding a Games panel to Edge. As discovered by reliable Redditor u/Leopeva64-2, Edge Canary now has an Appearance toggle through which you can add a Games button on the omnibar, next to your address bar.
When you enable this toggle, you can click on the Games button to launch a panel on the right side of your browser window, showing you a list of games, many from MSN Games. These are divided into various categories like Microsoft classics, Arcade, Board & Card, Puzzle, Sports, Casual, and more. Clicking on any game will launch it directly in the browser.
Although we are on Edge Canary 99.0.1117.0, we do not have the Games panel as of yet to test its behavior. This also indicates that this is a part of Microsoft's controlled rollout strategy in which it downstreams features in a staggered manner before rolling it out generally. Speaking of which, it's unclear when or if this "capability" will eventually make its way to the Stable channel, but you can be sure that its introduction will be divisive.