I'm having an issue with implementing a line of trace visualizer due to the Y-axis positioning.

Hello,
I’m implementing a line trace using a render target. I generate line traces in a 360-degree direction relative to the character and draw meshes by manipulating ISMs at collision points. This is captured in a render target, which is then used in the material to mask out invisible areas. On the X-axis, the occluded areas stay fixed around the collision point even when the camera moves. However, on the Y-axis, the occlusion area shifts with the camera movement, which is causing an issue.

Is there anyone who can help with this?

Below is the referenced post, and the attached image shows the material nodes used to adjust the render target’s size and UVs.
TUTORIAL: Line of Sight Visualizer for Unreal Engine | by Christian Sparks | Medium

The main camera is using an Ortho Camera.

Hard to tell with so little information. This tutorial is very interesting in my opinion. The effect on the other hand is not so simple, there is a lot of room for making mistakes along the way.

I suggest to check whether the RT-texture behaves the right way first. If you are 100% sure it does, you could try changing the camera mode from orthogonal back to its original settings, but I doubt that would make a difference.
There is just too little information to tell whats going on. Also it would help if you were showing the artifacts you are getting.

Other than that I can only recommend to check the tutorial and do it step-by-step to make sure everything is working correctly. Starting all over again does help sometimes even tho it takes a lot.

EDIT: I noticed that they are doing it completely different than you, is there a reason you are not following the tutorial on this part when it seems to work according to the tutorial?

It is Unreal Engine 4, but should be the same for UE5 in my opinion.