Just a simple experiment, put whatever 2D content you want on the wall.
bepis
portal hub2
Portal into Babylon.js worlds, demos taken from http://babylonjs.com/
Use arrow keys to move around.
https://www.babylonjs.com/demos/mansion/
snowy house
Credits to 3D scans
#21 - Footprints on a frozen lake, Wisconsin by WizardofAz (https://sketchfab.com/models/775f640f147648f890625ceff6ebd56e)
#17 - Monteverde's 'Columbus as a boy' (1872) by WizardofAz (https://sketchfab.com/models/2105b9c3bd184e4583133dca3365dbee)
#18 - Gingerbread House by WizardofAz (https://sketchfab.com/models/d70fb070ae1e441482ff4d4fd1d1f1d0)
Tanks Desert
Plain desert template for level building on. Scene is exported from Tanks! unity tutorial.
Unity Tanks
Tanks! demo scene exported from Unity by following this guide: http://janusvr.com/blog/other/unity.html
View the whole imgur album here: https://imgur.com/a/zNZv7
More info on Unity - WebVR
https://hacks.mozilla.org/2018/02/create-vr-on-the-web-using-unity3d/