Sniper Elite 5 will be available on Steam, Windows Store, Xbox Game Pass, Xbox One, Xbox Series X|S and PlayStation 4 & 5.
There are no concrete plans for a Switch version of Sniper Elite 5 at this point in time.
*If you have pre-ordered through Epic, you should have received a refund - if not, please reach out to them here: https://www.epicgames.com/help/en-US/contact-us*