Hello TakeTimeGames,
I went ahead and made a quick example of one way you could use a single line trace to determine if you can see an object. This example should give you a starting point. I hope that this information helps.
Example:
In short this uses a single line trace to form a grid that’s size is determined by the bound of the object you are looking for. This is done by preforming a line trace starting the top of your screen to the top of the object and lerping to a line trace from the bottom of your screen to the bottom of the object. Each time this line trace completes a lerp it will move from side to side one step at a time and perform the vertical sweep again.
The second part of this blueprint checks to see if the object is roughly within the frustum of the camera. It does this by converting the location of the object to screen space and then it checks to see if that screen space location is on screen.
The final check looks to see if the object is within the viewport and if one of the line traces have hit the object that you are looking for. If this returns true then the object can be seen.
Make it a great day