Are you talking about the lines and circle graphics when you are scoped in?
https://www.ultimateready.com/wp-content/uploads/2017/08/widowmaker0.jpg
This is the styled graphics as if you are looking through an actual telescoping lens on the Widow’s Kiss sniper rifle. For the most part they are stylized effects though some do use them to help align their aim in addition to the player crosshair setting.
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