I just installed Overwatch 2 to see what the problem is. Man, Blizzard make you jump through hoops to even get to the main menu.
Testing this on an oc'd Ryzen 3 3300X -- a 4c/8t SKU whose ST performance about matches the OP's i5-1135G7, though with 20-40% better MT. This is a desktop CPU, and I'm not thermally or power constrained.
Immediately after the installation I saw elevated CPU usage in the game for about six minutes, with initial total load at 100%. On each subsequent launch CPU utilization in the menu is as follows, with a 57 fps cap:
High CPU usage on initial game launch (or following a major update) is typical of most new games. As has been suggested, clock throttling at full load usually indicates insufficient cooling, but may also be the result of boost/power limits set in the BIOS.
To the OP, if your laptop shows normal temps in regular use, my advice would be to wait out the initial heavy loading of the CPU in the main menu, upon launching the game. Join a match only after CPU utilization goes back to low to avoid unwanted fps drops in-game.