They both bring their own ideas, but the modern hitmans and sniper elite are both big 3D games built around stealth as a core part of the gameplay loop.

Sniper elite leans into the sniper part as the primary gun (you can get a lower power ~~lower range~~ higher bullet drop silenced version, or you can gun and move before they triangulate you, or you can use other loud sources of sound to avoid triggering alerts), but you can do most to all of it with a pistol and knife if you want.

Hitman does the costume thing, but every level is designed with the intent of a "no extra kill, no alerts, no bodies found, suit only" challenge being possible.

In both cases the enemy AI (what makes a stealth game IMO) has a nice level of reaction to sounds/things they see, without just categorically abandoning their post to chase shadows, and once clearly sighted enemies can really swarm and escape gets super messy.