Hey there! How would I achieve this portal effect in Unreal, all help is appreciated, thanks!

[TobiasTobasco]

With some kind of parallax offset. E.g.:

Space Portal VFX Feedback

As I understand you want more depth in your elements that are rendered on a flat plane. Here is the material setup to get a soft parallax effect on your texturs by adding an inverted camera vector to texture coordinates. Tested example below. [idemoo] [giphy] [Portal_test UE 5]

Alternatively you can use custom depth with an actual tunnel mesh, similar to this:

UE4: Custom Depth Mask For a Crack in the Floor.