For me, the WALL function is not working as you show on the YouTube video.
I am new to Blender, so it may be me, doing something.
But I am copying what you are doing in the video, and not getting the same results.
I create a generic cube, so that the J menu works.
I hit J
This this auto create 2 walls/cubes, which are tangled together, and the edges are all messed up.
I tried with a plane, same results.
I will upload a picture, to better illustrate what is happening.
What am I doing wrong?
It is supposed to make a cube > into a hollow cube with walls right?
Default setings, this is my only addon
Latest Blender version
Latest BagaPie version