I see, thanks for your reply. I was probably asking for something out of scope for a PSX-like engine - per-texel lighting is far from common!
https://gamedev.stackexchange.com/questions/125437/per-texel-lighting-not-per-ve...
I'd have another question but I'm going to make it on the correct page (the PS1 engine: are the material graphs available for us to be customized? I'm assuming you're using a master material?).
When I watched the demo I couldn't but notice the Red Cross usage: maybe not you, but someone using that model could get into a few issues - I speak for personal experience :P
Geneva Conventions
It's an easy oversight but the red cross is veeery easy to trigger (Even Quake had to replace that symbol).