Need help: Render Target 2D X/Y dimensions, want to modify X and Y on EventOverlap to save on lag

I am attempting to create a “Portal” room that will behave as fast travel to other areas of the map, however with each new portal I implement, I lose approximately 10-15 FPS during gameplay. After some troubleshooting, I found that by changing the X and Y size dimensions of the Render Target from 1920x1080 down to 1x1, the lag is completely eliminated, however the portal visualization between each paired set of portals is also eliminated.

I would like to know how to be able to create x and y variables affecting each Render Target’s X+Y in blueprints, or if that is at all possible, so that I can then create an EventActorBegin/EndOverlap where when the portals are overlapped by the playercharacter, their Render Target dimensions are 1920x1080, and when the portals are not overlapped by the playercharacter, the Render Target dimensions are set to 1x1 in order to eliminate as much lag as possible. I would like the portals to effectively be “off” when the player is not near them.

If I find a solution to this before someone points me in the right (or better) direction, I’ll be sure to post it! Any lagless option is appreciated!