This is exactly what I was looking for. From lines 339-353 of your python file (https://gitlab.pavlovia.org/sabasiddique/face-reading-project/blob/master/MY%20TRUST%20GAME%201.6_lastrun.py) there’s this conditional statement that sets a value for demo_face_two and the like. It looks like that’s a custom code component. That is completely missing from the javascript file (https://gitlab.pavlovia.org/sabasiddique/face-reading-project/blob/master/html/MY%20TRUST%20GAME%201.6.js), which definitely explains why the variable isn’t defined.
It looks like that code component is in the “begin experiment” section of “face_demo” in python, but it was never converted to JS. So, make sure you’re using PsychoPy 2020.1.0 or later (the most recent is 2020.1.3), open that code component in the builder, and make sure code type is set to “auto->JS”, which should auto-convert that code component into javascript and include it in the javascript file. You should make sure all of your code components have been converted in that way, save and re-sync, and try the experiment again.